/*
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.
In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
For more information, please refer to
*/
#ifndef PIGPIO_H
#define PIGPIO_H
#include
#include
#define PIGPIO_VERSION 37
/*TEXT
pigpio is a C library for the Raspberry which allows control of the gpios.
*Features*
o PWM on any of gpios 0-31
o servo pulses on any of gpios 0-31
o callbacks when any of gpios 0-31 change state
o callbacks at timed intervals
o reading/writing all of the gpios in a bank as one operation
o individually setting gpio modes, reading and writing
o notifications when any of gpios 0-31 change state
o the construction of output waveforms with microsecond timing
o rudimentary permission control over gpios
o a simple interface to start and stop new threads
o I2C, SPI, and serial link wrappers
o creating and running scripts
*gpios*
ALL gpios are identified by their Broadcom number.
*Credits*
The PWM and servo pulses are timed using the DMA and PWM peripherals.
This use was inspired by Richard Hirst's servoblaster kernel module.
[https://github.com/richardghirst/PiBits/tree/master/ServoBlaster]
*Usage*
Include in your source files.
Assuming your source is in prog.c use the following command to build and
run the executable.
. .
gcc -o prog prog.c -lpigpio -lpthread -lrt
sudo ./prog
. .
For examples of usage see the C programs within the pigpio archive file.
*Notes*
All the functions which return an int return < 0 on error.
If the library is not initialised all but the [*gpioCfg**], [*gpioVersion*],
and [*gpioHardwareRevision*] functions will return PI_NOT_INITIALISED.
If the library is initialised the [*gpioCfg**] functions will
return PI_INITIALISED.
TEXT*/
/*OVERVIEW
ESSENTIAL
gpioInitialise Initialise library
gpioTerminate Stop library
BEGINNER
gpioSetMode Set a gpio mode
gpioGetMode Get a gpio mode
gpioSetPullUpDown Set/clear gpio pull up/down resistor
gpioRead Read a gpio
gpioWrite Write a gpio
gpioPWM Start/stop PWM pulses on a gpio
gpioGetPWMdutycycle Get dutycycle setting on a gpio
gpioServo Start/stop servo pulses on a gpio
gpioGetServoPulsewidth Get pulsewidth setting on a gpio
gpioDelay Delay for a number of microseconds
gpioSetAlertFunc Request a gpio level change callback
gpioSetTimerFunc Request a regular timed callback
INTERMEDIATE
gpioTrigger Send a trigger pulse to a gpio.
gpioSetWatchdog Set a watchdog on a gpio.
gpioSetPWMrange Configure PWM range for a gpio
gpioGetPWMrange Get configured PWM range for a gpio
gpioSetPWMfrequency Configure PWM frequency for a gpio
gpioGetPWMfrequency Get configured PWM frequency for a gpio
gpioRead_Bits_0_31 Read all gpios in bank 1
gpioRead_Bits_32_53 Read all gpios in bank 2
gpioWrite_Bits_0_31_Clear Clear selected gpios in bank 1
gpioWrite_Bits_32_53_Clear Clear selected gpios in bank 2
gpioWrite_Bits_0_31_Set Set selected gpios in bank 1
gpioWrite_Bits_32_53_Set Set selected gpios in bank 2
gpioStartThread Start a new thread
gpioStopThread Stop a previously started thread
ADVANCED
gpioGetPWMrealRange Get underlying PWM range for a gpio
gpioSetAlertFuncEx Request a gpio change callback, extended
gpioSetSignalFunc Request a signal callback
gpioSetSignalFuncEx Request a signal callback, extended
gpioSetGetSamplesFunc Requests a gpio samples callback
gpioSetGetSamplesFuncEx Requests a gpio samples callback, extended
gpioSetTimerFuncEx Request a regular timed callback, extended
gpioNotifyOpen Request a notification handle
gpioNotifyBegin Start notifications for selected gpios
gpioNotifyPause Pause notifications
gpioNotifyClose Close a notification
gpioSerialReadOpen Opens a gpio for bit bang serial reads
gpioSerialReadInvert Configures normal/inverted for serial reads
gpioSerialRead Reads bit bang serial data from a gpio
gpioSerialReadClose Closes a gpio for bit bang serial reads
gpioHardwareClock Start hardware clock on supported gpios
gpioHardwarePWM Start hardware PWM on supported gpios
SCRIPTS
gpioStoreScript Store a script
gpioRunScript Run a stored script
gpioScriptStatus Get script status and parameters
gpioStopScript Stop a running script
gpioDeleteScript Delete a stored script
WAVES
gpioWaveClear Deletes all waveforms
gpioWaveAddNew Starts a new waveform
gpioWaveAddGeneric Adds a series of pulses to the waveform
gpioWaveAddSerial Adds serial data to the waveform
gpioWaveCreate Creates a waveform from added data
gpioWaveDelete Deletes a waveform
gpioWaveTxSend Transmits a waveform
gpioWaveChain Transmits a chain of waveforms
gpioWaveTxBusy Checks to see if the waveform has ended
gpioWaveTxStop Aborts the current waveform
gpioWaveGetMicros Length in microseconds of the current waveform
gpioWaveGetHighMicros Length of longest waveform so far
gpioWaveGetMaxMicros Absolute maximum allowed micros
gpioWaveGetPulses Length in pulses of the current waveform
gpioWaveGetHighPulses Length of longest waveform so far
gpioWaveGetMaxPulses Absolute maximum allowed pulses
gpioWaveGetCbs Length in control blocks of the current waveform
gpioWaveGetHighCbs Length of longest waveform so far
gpioWaveGetMaxCbs Absolute maximum allowed control blocks
I2C
i2cOpen Opens an I2C device
i2cClose Closes an I2C device
i2cWriteQuick SMBus write quick
i2cWriteByte SMBus write byte
i2cReadByte SMBus read byte
i2cWriteByteData SMBus write byte data
i2cWriteWordData SMBus write word data
i2cReadByteData SMBus read byte data
i2cReadWordData SMBus read word data
i2cProcessCall SMBus process call
i2cWriteBlockData SMBus write block data
i2cReadBlockData SMBus read block data
i2cBlockProcessCall SMBus block process call
i2cWriteI2CBlockData SMBus write I2C block data
i2cReadI2CBlockData SMBus read I2C block data
i2cReadDevice Reads the raw I2C device
i2cWriteDevice Writes the raw I2C device
i2cSwitchCombined Sets or clears the combined flag
i2cSegments Performs multiple I2C transactions
i2cZip Performs multiple I2C transactions
bbI2COpen Opens gpios for bit banging I2C
bbI2CClose Closes gpios for bit banging I2C
bbI2CZip Performs multiple bit banged I2C transactions
SPI
spiOpen Opens a SPI device
spiClose Closes a SPI device
spiRead Reads bytes from a SPI device
spiWrite Writes bytes to a SPI device
spiXfer Transfers bytes with a SPI device
SERIAL
serOpen Opens a serial device (/dev/tty*)
serClose Closes a serial device
serWriteByte Writes a byte to a serial device
serReadByte Reads a byte from a serial device
serWrite Writes bytes to a serial device
serRead Reads bytes from a serial device
serDataAvailable Returns number of bytes ready to be read
CONFIGURATION
gpioCfgBufferSize Configure the gpio sample buffer size
gpioCfgClock Configure the gpio sample rate
gpioCfgDMAchannel Configure the DMA channel (DEPRECATED)
gpioCfgDMAchannels Configure the DMA channels
gpioCfgPermissions Configure the gpio access permissions
gpioCfgInterfaces Configure user interfaces
gpioCfgInternals Configure miscellaneous internals
gpioCfgSocketPort Configure socket port
gpioCfgMemAlloc Configure DMA memory allocation mode
CUSTOM
gpioCustom1 User custom function 1
gpioCustom2 User custom function 2
UTILITIES
gpioTick Get current tick (microseconds)
gpioHardwareRevision Get hardware revision
gpioVersion Get the pigpio version
getBitInBytes Get the value of a bit
putBitInBytes Set the value of a bit
gpioTime Get current time
gpioSleep Sleep for specified time
time_sleep Sleeps for a float number of seconds
time_time Float number of seconds since the epoch
EXPERT
rawWaveAddSPI Not intended for general use
rawWaveAddGeneric Not intended for general use
rawWaveCB Not intended for general use
rawWaveCBAdr Not intended for general use
rawWaveGetOut Not intended for general use
rawWaveSetOut Not intended for general use
rawWaveGetIn Not intended for general use
rawWaveSetIn Not intended for general use
rawWaveInfo Not intended for general use
rawDumpWave Not intended for general use
rawDumpScript Not intended for general use
OVERVIEW*/
#define PI_INPFIFO "/dev/pigpio"
#define PI_OUTFIFO "/dev/pigout"
#define PI_ERRFIFO "/dev/pigerr"
#define PI_ENVPORT "PIGPIO_PORT"
#define PI_ENVADDR "PIGPIO_ADDR"
#define PI_LOCKFILE "/var/run/pigpio.pid"
#define PI_I2C_COMBINED "/sys/module/i2c_bcm2708/parameters/combined"
#ifdef __cplusplus
extern "C" {
#endif
typedef struct
{
uint16_t func;
uint16_t size;
} gpioHeader_t;
typedef struct
{
size_t size;
void *ptr;
uint32_t data;
} gpioExtent_t;
typedef struct
{
uint32_t tick;
uint32_t level;
} gpioSample_t;
typedef struct
{
uint16_t seqno;
uint16_t flags;
uint32_t tick;
uint32_t level;
} gpioReport_t;
typedef struct
{
uint32_t gpioOn;
uint32_t gpioOff;
uint32_t usDelay;
} gpioPulse_t;
#define WAVE_FLAG_READ 1
#define WAVE_FLAG_TICK 2
typedef struct
{
uint32_t gpioOn;
uint32_t gpioOff;
uint32_t usDelay;
uint32_t flags;
} rawWave_t;
/*
CBs are used in order from the lowest numbered CB up to
the maximum NUM_WAVE_CBS.
OOLS are used from the bottom climbing up and from
the top climbing down.
The gpio on and off settings climb up from the bottom (botOOL/numBOOL).
The level and tick read values are stored in descending locations
from the top (topOOL/numTOOL).
*/
typedef struct
{
uint16_t botCB; /* first CB used by wave */
uint16_t topCB; /* last CB used by wave */
uint16_t botOOL; /* first bottom OOL used by wave */
/* botOOL to botOOL + numBOOL -1 are in use */
uint16_t topOOL; /* last top OOL used by wave */
/* topOOL - numTOOL to topOOL are in use.*/
uint16_t deleted;
uint16_t numCB;
uint16_t numBOOL;
uint16_t numTOOL;
} rawWaveInfo_t;
typedef struct
{
int clk; /* gpio for clock */
int mosi; /* gpio for MOSI */
int miso; /* gpio for MISO */
int ss_pol; /* slave select off state */
int ss_us; /* delay after slave select */
int clk_pol; /* clock off state */
int clk_pha; /* clock phase */
int clk_us; /* clock micros */
} rawSPI_t;
typedef struct { /* linux/arch/arm/mach-bcm2708/include/mach/dma.h */
uint32_t info;
uint32_t src;
uint32_t dst;
uint32_t length;
uint32_t stride;
uint32_t next;
uint32_t pad[2];
} rawCbs_t;
typedef struct
{
uint16_t addr; /* slave address */
uint16_t flags;
uint16_t len; /* msg length */
uint8_t *buf; /* pointer to msg data */
} pi_i2c_msg_t;
typedef void (*gpioAlertFunc_t) (int gpio,
int level,
uint32_t tick);
typedef void (*gpioAlertFuncEx_t) (int gpio,
int level,
uint32_t tick,
void *userdata);
typedef void (*gpioTimerFunc_t) (void);
typedef void (*gpioTimerFuncEx_t) (void *userdata);
typedef void (*gpioSignalFunc_t) (int signum);
typedef void (*gpioSignalFuncEx_t) (int signum,
void *userdata);
typedef void (*gpioGetSamplesFunc_t) (const gpioSample_t *samples,
int numSamples);
typedef void (*gpioGetSamplesFuncEx_t) (const gpioSample_t *samples,
int numSamples,
void *userdata);
typedef void *(gpioThreadFunc_t) (void *);
/* gpio: 0-53 */
#define PI_MIN_GPIO 0
#define PI_MAX_GPIO 53
/* user_gpio: 0-31 */
#define PI_MAX_USER_GPIO 31
/* level: 0-1 */
#define PI_OFF 0
#define PI_ON 1
#define PI_CLEAR 0
#define PI_SET 1
#define PI_LOW 0
#define PI_HIGH 1
/* level: only reported for gpio time-out, see gpioSetWatchdog */
#define PI_TIMEOUT 2
/* mode: 0-7 */
#define PI_INPUT 0
#define PI_OUTPUT 1
#define PI_ALT0 4
#define PI_ALT1 5
#define PI_ALT2 6
#define PI_ALT3 7
#define PI_ALT4 3
#define PI_ALT5 2
/* pud: 0-2 */
#define PI_PUD_OFF 0
#define PI_PUD_DOWN 1
#define PI_PUD_UP 2
/* dutycycle: 0-range */
#define PI_DEFAULT_DUTYCYCLE_RANGE 255
/* range: 25-40000 */
#define PI_MIN_DUTYCYCLE_RANGE 25
#define PI_MAX_DUTYCYCLE_RANGE 40000
/* pulsewidth: 0, 500-2500 */
#define PI_SERVO_OFF 0
#define PI_MIN_SERVO_PULSEWIDTH 500
#define PI_MAX_SERVO_PULSEWIDTH 2500
/* hardware PWM */
#define PI_HW_PWM_MIN_FREQ 1
#define PI_HW_PWM_MAX_FREQ 125000000
#define PI_HW_PWM_RANGE 1000000
/* hardware clock */
#define PI_HW_CLK_MIN_FREQ 4689
#define PI_HW_CLK_MAX_FREQ 250000000
#define PI_NOTIFY_SLOTS 32
#define PI_NTFY_FLAGS_ALIVE (1 <<6)
#define PI_NTFY_FLAGS_WDOG (1 <<5)
#define PI_NTFY_FLAGS_BIT(x) (((x)<<0)&31)
#define PI_WAVE_BLOCKS 4
#define PI_WAVE_MAX_PULSES (PI_WAVE_BLOCKS * 3000)
#define PI_WAVE_MAX_CHARS (PI_WAVE_BLOCKS * 300)
#define PI_BB_I2C_MIN_BAUD 50
#define PI_BB_I2C_MAX_BAUD 500000
#define PI_BB_SER_MIN_BAUD 50
#define PI_BB_SER_MAX_BAUD 250000
#define PI_BB_SER_NORMAL 0
#define PI_BB_SER_INVERT 1
#define PI_WAVE_MIN_BAUD 50
#define PI_WAVE_MAX_BAUD 1000000
//#define PI_SPI_MIN_BAUD 32000
//#define PI_SPI_MAX_BAUD 125000000
#define PI_SPI_MIN_BAUD 1
#define PI_SPI_MAX_BAUD 500000000
#define PI_MIN_WAVE_DATABITS 1
#define PI_MAX_WAVE_DATABITS 32
#define PI_MIN_WAVE_HALFSTOPBITS 2
#define PI_MAX_WAVE_HALFSTOPBITS 8
#define PI_WAVE_MAX_MICROS (30 * 60 * 1000000) /* half an hour */
#define PI_MAX_WAVES 250
#define PI_MAX_WAVE_CYCLES 65535
#define PI_MAX_WAVE_DELAY 65535
#define PI_WAVE_COUNT_PAGES 10
/* wave tx mode */
#define PI_WAVE_MODE_ONE_SHOT 0
#define PI_WAVE_MODE_REPEAT 1
/* I2C, SPI, SER */
#define PI_I2C_SLOTS 32
#define PI_SPI_SLOTS 16
#define PI_SER_SLOTS 8
#define PI_NUM_I2C_BUS 2
#define PI_MAX_I2C_ADDR 0x7F
#define PI_NUM_AUX_SPI_CHANNEL 3
#define PI_NUM_STD_SPI_CHANNEL 2
#define PI_MAX_I2C_DEVICE_COUNT (1<<16)
#define PI_MAX_SPI_DEVICE_COUNT (1<<16)
/* max pi_i2c_msg_t per transaction */
#define PI_I2C_RDRW_IOCTL_MAX_MSGS 42
/* flags for i2cTransaction, pi_i2c_msg_t */
#define PI_I2C_M_WR 0x0000 /* write data */
#define PI_I2C_M_RD 0x0001 /* read data */
#define PI_I2C_M_TEN 0x0010 /* ten bit chip address */
#define PI_I2C_M_RECV_LEN 0x0400 /* length will be first received byte */
#define PI_I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */
#define PI_I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
#define PI_I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */
#define PI_I2C_M_NOSTART 0x4000 /* if I2C_FUNC_PROTOCOL_MANGLING */
/* bbI2CZip and i2cZip commands */
#define PI_I2C_END 0
#define PI_I2C_ESC 1
#define PI_I2C_START 2
#define PI_I2C_COMBINED_ON 2
#define PI_I2C_STOP 3
#define PI_I2C_COMBINED_OFF 3
#define PI_I2C_ADDR 4
#define PI_I2C_FLAGS 5
#define PI_I2C_READ 6
#define PI_I2C_WRITE 7
/* SPI */
#define PI_SPI_FLAGS_BITLEN(x) ((x&63)<<16)
#define PI_SPI_FLAGS_RX_LSB(x) ((x&1)<<15)
#define PI_SPI_FLAGS_TX_LSB(x) ((x&1)<<14)
#define PI_SPI_FLAGS_3WREN(x) ((x&15)<<10)
#define PI_SPI_FLAGS_3WIRE(x) ((x&1)<<9)
#define PI_SPI_FLAGS_AUX_SPI(x) ((x&1)<<8)
#define PI_SPI_FLAGS_RESVD(x) ((x&7)<<5)
#define PI_SPI_FLAGS_CSPOLS(x) ((x&7)<<2)
#define PI_SPI_FLAGS_MODE(x) ((x&3))
/* Longest busy delay */
#define PI_MAX_BUSY_DELAY 100
/* timeout: 0-60000 */
#define PI_MIN_WDOG_TIMEOUT 0
#define PI_MAX_WDOG_TIMEOUT 60000
/* timer: 0-9 */
#define PI_MIN_TIMER 0
#define PI_MAX_TIMER 9
/* millis: 10-60000 */
#define PI_MIN_MS 10
#define PI_MAX_MS 60000
#define PI_MAX_SCRIPTS 32
#define PI_MAX_SCRIPT_TAGS 50
#define PI_MAX_SCRIPT_VARS 150
#define PI_MAX_SCRIPT_PARAMS 10
/* script status */
#define PI_SCRIPT_INITING 0
#define PI_SCRIPT_HALTED 1
#define PI_SCRIPT_RUNNING 2
#define PI_SCRIPT_WAITING 3
#define PI_SCRIPT_FAILED 4
/* signum: 0-63 */
#define PI_MIN_SIGNUM 0
#define PI_MAX_SIGNUM 63
/* timetype: 0-1 */
#define PI_TIME_RELATIVE 0
#define PI_TIME_ABSOLUTE 1
#define PI_MAX_MICS_DELAY 1000000 /* 1 second */
#define PI_MAX_MILS_DELAY 60000 /* 60 seconds */
/* cfgMillis */
#define PI_BUF_MILLIS_MIN 100
#define PI_BUF_MILLIS_MAX 10000
/* cfgMicros: 1, 2, 4, 5, 8, or 10 */
/* cfgPeripheral: 0-1 */
#define PI_CLOCK_PWM 0
#define PI_CLOCK_PCM 1
/* DMA channel: 0-14 */
#define PI_MIN_DMA_CHANNEL 0
#define PI_MAX_DMA_CHANNEL 14
#define PI_MAX_PRIMARY_CHANNEL 14
#define PI_MAX_SECONDARY_CHANNEL 6
/* port */
#define PI_MIN_SOCKET_PORT 1024
#define PI_MAX_SOCKET_PORT 32000
/* ifFlags: */
#define PI_DISABLE_FIFO_IF 1
#define PI_DISABLE_SOCK_IF 2
/* memAllocMode */
#define PI_MEM_ALLOC_AUTO 0
#define PI_MEM_ALLOC_PAGEMAP 1
#define PI_MEM_ALLOC_MAILBOX 2
/*F*/
int gpioInitialise(void);
/*D
Initialises the library.
Call before using the other library functions.
Returns the pigpio version number if OK, otherwise PI_INIT_FAILED.
The only exception is the optional [*gpioCfg**] functions, see later.
...
if (gpioInitialise() < 0)
{
// pigpio initialisation failed.
}
else
{
// pigpio initialised okay.
}
...
D*/
/*F*/
void gpioTerminate(void);
/*D
Terminates the library.
Returns nothing.
Call before program exit.
This function resets the used DMA channels, releases memory, and
terminates any running threads.
...
gpioTerminate();
...
D*/
/*F*/
int gpioSetMode(unsigned gpio, unsigned mode);
/*D
Sets the gpio mode, typically input or output.
. .
gpio: 0-53
mode: 0-7
. .
Returns 0 if OK, otherwise PI_BAD_GPIO or PI_BAD_MODE.
Arduino style: pinMode.
...
gpioSetMode(17, PI_INPUT); // Set gpio17 as input.
gpioSetMode(18, PI_OUTPUT); // Set gpio18 as output.
gpioSetMode(22,PI_ALT0); // Set gpio22 to alternative mode 0.
...
D*/
/*F*/
int gpioGetMode(unsigned gpio);
/*D
Gets the gpio mode.
. .
gpio: 0-53
. .
Returns the gpio mode if OK, otherwise PI_BAD_GPIO.
...
if (gpioGetMode(17) != PI_ALT0)
{
gpioSetMode(17, PI_ALT0); // set gpio17 to ALT0
}
...
D*/
/*F*/
int gpioSetPullUpDown(unsigned gpio, unsigned pud);
/*D
Sets or clears resistor pull ups or downs on the gpio.
. .
gpio: 0-53
pud: 0-2
. .
Returns 0 if OK, otherwise PI_BAD_GPIO or PI_BAD_PUD.
...
gpioSetPullUpDown(17, PI_PUD_UP); // Sets a pull-up.
gpioSetPullUpDown(18, PI_PUD_DOWN); // Sets a pull-down.
gpioSetPullUpDown(23, PI_PUD_OFF); // Clear any pull-ups/downs.
...
D*/
/*F*/
int gpioRead (unsigned gpio);
/*D
Reads the gpio level, on or off.
. .
gpio: 0-53
. .
Returns the gpio level if OK, otherwise PI_BAD_GPIO.
Arduino style: digitalRead.
...
printf("gpio24 is level %d\n", gpioRead(24));
...
D*/
/*F*/
int gpioWrite(unsigned gpio, unsigned level);
/*D
Sets the gpio level, on or off.
. .
gpio: 0-53
level: 0,1
. .
Returns 0 if OK, otherwise PI_BAD_GPIO or PI_BAD_LEVEL.
If PWM or servo pulses are active on the gpio they are switched off.
Arduino style: digitalWrite
...
gpioWrite(24, 1); // Set gpio24 high.
...
D*/
/*F*/
int gpioPWM(unsigned user_gpio, unsigned dutycycle);
/*D
Starts PWM on the gpio, dutycycle between 0 (off) and range (fully on).
Range defaults to 255.
. .
user_gpio: 0-31
dutycycle: 0-range
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO or PI_BAD_DUTYCYCLE.
Arduino style: analogWrite
This and the servo functionality use the DMA and PWM or PCM peripherals
to control and schedule the pulse lengths and dutycycles.
The [*gpioSetPWMrange*] function may be used to change the default
range of 255.
...
gpioPWM(17, 255); // Sets gpio17 full on.
gpioPWM(18, 128); // Sets gpio18 half on.
gpioPWM(23, 0); // Sets gpio23 full off.
...
D*/
/*F*/
int gpioGetPWMdutycycle(unsigned user_gpio);
/*D
Returns the PWM dutycycle setting for the gpio.
. .
user_gpio: 0-31
. .
Returns between 0 (off) and range (fully on) if OK, otherwise
PI_BAD_USER_GPIO or PI_NOT_PWM_GPIO.
For normal PWM the dutycycle will be out of the defined range
for the gpio (see [*gpioGetPWMrange*]).
If a hardware clock is active on the gpio the reported dutycycle
will be 500000 (500k) out of 1000000 (1M).
If hardware PWM is active on the gpio the reported dutycycle
will be out of a 1000000 (1M).
Normal PWM range defaults to 255.
D*/
/*F*/
int gpioSetPWMrange(unsigned user_gpio, unsigned range);
/*D
Selects the dutycycle range to be used for the gpio. Subsequent calls
to gpioPWM will use a dutycycle between 0 (off) and range (fully on).
. .
user_gpio: 0-31
range: 25-40000
. .
Returns the real range for the given gpio's frequency if OK,
otherwise PI_BAD_USER_GPIO or PI_BAD_DUTYRANGE.
If PWM is currently active on the gpio its dutycycle will be scaled
to reflect the new range.
The real range, the number of steps between fully off and fully
on for each frequency, is given in the following table.
. .
25, 50, 100, 125, 200, 250, 400, 500, 625,
800, 1000, 1250, 2000, 2500, 4000, 5000, 10000, 20000
. .
The real value set by [*gpioPWM*] is (dutycycle * real range) / range.
...
gpioSetPWMrange(24, 2000); // Now 2000 is fully on
// 1000 is half on
// 500 is quarter on, etc.
...
D*/
/*F*/
int gpioGetPWMrange(unsigned user_gpio);
/*D
Returns the dutycycle range used for the gpio if OK, otherwise
PI_BAD_USER_GPIO.
. .
user_gpio: 0-31
. .
If a hardware clock or hardware PWM is active on the gpio
the reported range will be 1000000 (1M).
...
r = gpioGetPWMrange(23);
...
D*/
/*F*/
int gpioGetPWMrealRange(unsigned user_gpio);
/*D
Returns the real range used for the gpio if OK, otherwise
PI_BAD_USER_GPIO.
. .
user_gpio: 0-31
. .
If a hardware clock is active on the gpio the reported real
range will be 1000000 (1M).
If hardware PWM is active on the gpio the reported real range
will be approximately 250M divided by the set PWM frequency.
...
rr = gpioGetPWMrealRange(17);
...
D*/
/*F*/
int gpioSetPWMfrequency(unsigned user_gpio, unsigned frequency);
/*D
Sets the frequency in hertz to be used for the gpio.
. .
user_gpio: 0-31
frequency: >=0
. .
Returns the numerically closest frequency if OK, otherwise
PI_BAD_USER_GPIO.
The selectable frequencies depend upon the sample rate which
may be 1, 2, 4, 5, 8, or 10 microseconds (default 5).
Each gpio can be independently set to one of 18 different PWM
frequencies.
If PWM is currently active on the gpio it will be
switched off and then back on at the new frequency.
The frequencies for each sample rate are:
. .
Hertz
1: 40000 20000 10000 8000 5000 4000 2500 2000 1600
1250 1000 800 500 400 250 200 100 50
2: 20000 10000 5000 4000 2500 2000 1250 1000 800
625 500 400 250 200 125 100 50 25
4: 10000 5000 2500 2000 1250 1000 625 500 400
313 250 200 125 100 63 50 25 13
sample
rate
(us) 5: 8000 4000 2000 1600 1000 800 500 400 320
250 200 160 100 80 50 40 20 10
8: 5000 2500 1250 1000 625 500 313 250 200
156 125 100 63 50 31 25 13 6
10: 4000 2000 1000 800 500 400 250 200 160
125 100 80 50 40 25 20 10 5
. .
...
gpioSetPWMfrequency(23, 0); // Set gpio23 to lowest frequency.
gpioSetPWMfrequency(24, 500); // Set gpio24 to 500Hz.
gpioSetPWMfrequency(25, 100000); // Set gpio25 to highest frequency.
...
D*/
/*F*/
int gpioGetPWMfrequency(unsigned user_gpio);
/*D
Returns the frequency (in hertz) used for the gpio if OK, otherwise
PI_BAD_USER_GPIO.
. .
user_gpio: 0-31
. .
For normal PWM the frequency will be that defined for the gpio by
[*gpioSetPWMfrequency*].
If a hardware clock is active on the gpio the reported frequency
will be that set by [*gpioHardwareClock*].
If hardware PWM is active on the gpio the reported frequency
will be that set by [*gpioHardwarePWM*].
...
f = gpioGetPWMfrequency(23); // Get frequency used for gpio23.
...
D*/
/*F*/
int gpioServo(unsigned user_gpio, unsigned pulsewidth);
/*D
Starts servo pulses on the gpio, 0 (off), 500 (most anti-clockwise) to
2500 (most clockwise).
. .
user_gpio: 0-31
pulsewidth: 0, 500-2500
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO or PI_BAD_PULSEWIDTH.
The range supported by servos varies and should probably be determined
by experiment. A value of 1500 should always be safe and represents
the mid-point of rotation. You can DAMAGE a servo if you command it
to move beyond its limits.
The following causes an on pulse of 1500 microseconds duration to be
transmitted on gpio 17 at a rate of 50 times per second. This will
command a servo connected to gpio 17 to rotate to its mid-point.
...
gpioServo(17, 1000); // Move servo to safe position anti-clockwise.
gpioServo(23, 1500); // Move servo to centre position.
gpioServo(25, 2000); // Move servo to safe position clockwise.
...
OTHER UPDATE RATES:
This function updates servos at 50Hz. If you wish to use a different
update frequency you will have to use the PWM functions.
. .
PWM Hz 50 100 200 400 500
1E6/Hz 20000 10000 5000 2500 2000
. .
Firstly set the desired PWM frequency using [*gpioSetPWMfrequency*].
Then set the PWM range using [*gpioSetPWMrange*] to 1E6/frequency.
Doing this allows you to use units of microseconds when setting
the servo pulsewidth.
E.g. If you want to update a servo connected to gpio25 at 400Hz
. .
gpioSetPWMfrequency(25, 400);
gpioSetPWMrange(25, 2500);
. .
Thereafter use the PWM command to move the servo,
e.g. gpioPWM(25, 1500) will set a 1500 us pulse.
D*/
/*F*/
int gpioGetServoPulsewidth(unsigned user_gpio);
/*D
Returns the servo pulsewidth setting for the gpio.
. .
user_gpio: 0-31
. .
Returns , 0 (off), 500 (most anti-clockwise) to 2500 (most clockwise)
if OK, otherwise PI_BAD_USER_GPIO or PI_NOT_SERVO_GPIO.
D*/
/*F*/
int gpioSetAlertFunc(unsigned user_gpio, gpioAlertFunc_t f);
/*D
Registers a function to be called (a callback) when the specified
gpio changes state.
. .
user_gpio: 0-31
f: the callback function
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO.
One function may be registered per gpio.
The function is passed the gpio, the new level, and the tick.
The alert may be cancelled by passing NULL as the function.
The gpios are sampled at a rate set when the library is started.
If a value isn't specifically set the default of 5 us is used.
The number of samples per second is given in the following table.
. .
samples
per sec
1 1,000,000
2 500,000
sample 4 250,000
rate 5 200,000
(us) 8 125,000
10 100,000
. .
Level changes shorter than the sample rate may be missed.
The thread which calls the alert functions is triggered nominally
1000 times per second. The active alert functions will be called
once per level change since the last time the thread was activated.
i.e. The active alert functions will get all level changes but there
will be a latency.
The tick value is the time stamp of the sample in microseconds, see
[*gpioTick*] for more details.
...
void aFunction(int gpio, int level, uint32_t tick)
{
printf("gpio %d became %d at %d\n", gpio, level, tick);
}
// call aFunction whenever gpio 4 changes state
gpioSetAlertFunc(4, aFunction);
...
D*/
/*F*/
int gpioSetAlertFuncEx(
unsigned user_gpio, gpioAlertFuncEx_t f, void *userdata);
/*D
Registers a function to be called (a callback) when the specified
gpio changes state.
. .
user_gpio: 0-31
f: the callback function
userdata: pointer to arbitrary user data
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO.
One function may be registered per gpio.
The function is passed the gpio, the new level, the tick, and
the userdata pointer.
Only one of [*gpioSetAlertFunc*] or [*gpioSetAlertFuncEx*] can be
registered per gpio.
See [*gpioSetAlertFunc*] for further details.
D*/
/*F*/
int gpioNotifyOpen(void);
/*D
This function requests a free notification handle.
Returns a handle greater than or equal to zero if OK,
otherwise PI_NO_HANDLE.
A notification is a method for being notified of gpio state changes
via a pipe or socket.
Pipe notifications for handle x will be available at the pipe
named /dev/pigpiox (where x is the handle number). E.g. if the
function returns 15 then the notifications must be read
from /dev/pigpio15.
Socket notifications are returned to the socket which requested the
handle.
...
h = gpioNotifyOpen();
if (h >= 0)
{
sprintf(str, "/dev/pigpio%d", h);
fd = open(str, "r");
if (fd >= 0)
{
// Okay.
}
else
{
// Error.
}
}
else
{
// Error.
}
...
D*/
/*F*/
int gpioNotifyBegin(unsigned handle, uint32_t bits);
/*D
This function starts notifications on a previously opened handle.
. .
handle: >=0, as returned by [*gpioNotifyOpen*]
bits: a bit mask indicating the gpios of interest
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE.
The notification sends state changes for each gpio whose corresponding
bit in bits is set.
Each notification occupies 12 bytes in the fifo and has the
following structure.
. .
typedef struct
{
uint16_t seqno;
uint16_t flags;
uint32_t tick;
uint32_t level;
} gpioReport_t;
. .
seqno: starts at 0 each time the handle is opened and then increments
by one for each report.
flags: two flags are defined, PI_NTFY_FLAGS_WDOG and PI_NTFY_FLAGS_ALIVE.
If bit 5 is set (PI_NTFY_FLAGS_WDOG) then bits 0-4 of the flags
indicate a gpio which has had a watchdog timeout; if bit 6 is set
(PI_NTFY_FLAGS_ALIVE) this indicates a keep alive signal on the
pipe/socket and is sent once a minute in the absence of other
notification activity.
tick: the number of microseconds since system boot. It wraps around
after 1h12m.
level: indicates the level of each gpio. If bit 1<=0, as returned by [*gpioNotifyOpen*]
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE.
Notifications for the handle are suspended until [*gpioNotifyBegin*]
is called again.
...
gpioNotifyPause(h);
...
D*/
/*F*/
int gpioNotifyClose(unsigned handle);
/*D
This function stops notifications on a previously opened handle
and releases the handle for reuse.
. .
handle: >=0, as returned by [*gpioNotifyOpen*]
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE.
...
gpioNotifyClose(h);
...
D*/
/*F*/
int gpioWaveClear(void);
/*D
This function clears all waveforms and any data added by calls to the
[*gpioWaveAdd**] functions.
Returns 0 if OK.
...
gpioWaveClear();
...
D*/
/*F*/
int gpioWaveAddNew(void);
/*D
This function starts a new empty waveform.
You wouldn't normally need to call this function as it is automatically
called after a waveform is created with the [*gpioWaveCreate*] function.
Returns 0 if OK.
...
gpioWaveAddNew();
...
D*/
/*F*/
int gpioWaveAddGeneric(unsigned numPulses, gpioPulse_t *pulses);
/*D
This function adds a number of pulses to the current waveform.
. .
numPulses: the number of pulses
pulses: an array of pulses
. .
Returns the new total number of pulses in the current waveform if OK,
otherwise PI_TOO_MANY_PULSES.
The pulses are interleaved in time order within the existing waveform
(if any).
Merging allows the waveform to be built in parts, that is the settings
for gpio#1 can be added, and then gpio#2 etc.
If the added waveform is intended to start after or within the existing
waveform then the first pulse should consist of a delay.
...
// Construct and send a 30 microsecond square wave.
gpioSetMode(gpio, PI_OUTPUT);
pulse[0].gpioOn = (1<= 0)
{
gpioWaveTxSend(wave_id, PI_WAVE_MODE_REPEAT);
// Transmit for 30 seconds.
sleep(30);
gpioWaveTxStop();
}
else
{
// Wave create failed.
}
...
D*/
/*F*/
int gpioWaveAddSerial
(unsigned user_gpio,
unsigned baud,
unsigned data_bits,
unsigned stop_bits,
unsigned offset,
unsigned numBytes,
char *str);
/*D
This function adds a waveform representing serial data to the
existing waveform (if any). The serial data starts offset
microseconds from the start of the waveform.
. .
user_gpio: 0-31
baud: 50-1000000
data_bits: 1-32
stop_bits: 2-8
offset: 0-
numBytes: 1-
str: an array of chars (which may contain nulls)
. .
Returns the new total number of pulses in the current waveform if OK,
otherwise PI_BAD_USER_GPIO, PI_BAD_WAVE_BAUD, PI_BAD_DATABITS,
PI_BAD_STOPBITS, PI_TOO_MANY_CHARS, PI_BAD_SER_OFFSET,
or PI_TOO_MANY_PULSES.
NOTES:
The serial data is formatted as one start bit, data_bits data bits, and
stop_bits/2 stop bits.
It is legal to add serial data streams with different baud rates to
the same waveform.
numBytes is the number of bytes of data in str.
The bytes required for each character depend upon data_bits.
For data_bits 1-8 there will be one byte per character.
For data_bits 9-16 there will be two bytes per character.
For data_bits 17-32 there will be four bytes per character.
...
#define MSG_LEN 8
int i;
char *str;
char data[MSG_LEN];
str = "Hello world!";
gpioWaveAddSerial(4, 9600, 8, 2, 0, strlen(str), str);
for (i=0; i=0, as returned by [*gpioWaveCreate*]
. .
Wave ids are allocated in order, 0, 1, 2, etc.
Returns 0 if OK, otherwise PI_BAD_WAVE_ID.
D*/
/*F*/
int gpioWaveTxSend(unsigned wave_id, unsigned wave_mode);
/*D
This function transmits the waveform with id wave_id. The mode
determines whether the waveform is sent once or cycles endlessly.
NOTE: Any hardware PWM started by [*gpioHardwarePWM*] will be cancelled.
. .
wave_id: >=0, as returned by [*gpioWaveCreate*]
wave_mode: 0 (PI_WAVE_MODE_ONE_SHOT), 1 (PI_WAVE_MODE_REPEAT)
. .
Returns the number of DMA control blocks in the waveform if OK,
otherwise PI_BAD_WAVE_ID, or PI_BAD_WAVE_MODE.
D*/
/*F*/
int gpioWaveChain(char *buf, unsigned bufSize);
/*D
This function transmits a chain of waveforms.
NOTE: Any hardware PWM started by [*gpioHardwarePWM*] will be cancelled.
The waves to be transmitted are specified by the contents of buf
which contains an ordered list of [*wave_id*]s and optional command
codes and related data.
. .
buf: pointer to the wave_ids and optional command codes
bufSize: the number of bytes in buf
. .
Returns 0 if OK, otherwise PI_CHAIN_NESTING, PI_CHAIN_LOOP_CNT, PI_BAD_CHAIN_LOOP, PI_BAD_CHAIN_CMD, PI_CHAIN_COUNTER,
PI_BAD_CHAIN_DELAY, PI_CHAIN_TOO_BIG, or PI_BAD_WAVE_ID.
Each wave is transmitted in the order specified. A wave may
occur multiple times per chain.
A blocks of waves may be transmitted multiple times by using
the loop commands. The block is bracketed by loop start and
end commands. Loops may be nested.
Delays between waves may be added with the delay command.
The following command codes are supported:
Name @ Cmd & Data @ Meaning
Loop Start @ 255 0 @ Identify start of a wave block
Loop Repeat @ 255 1 x y @ loop x + y*256 times
Delay @ 255 2 x y @ delay x + y*256 microseconds
The code is currently dimensioned to support a chain with roughly
600 entries and 20 loop counters.
...
#include
#include
#define WAVES 5
#define GPIO 4
int main(int argc, char *argv[])
{
int i, wid[WAVES];
if (gpioInitialise()<0) return -1;
gpioSetMode(GPIO, PI_OUTPUT);
printf("start piscope, press return\n"); getchar();
for (i=0; i=0) if OK, otherwise PI_BAD_I2C_BUS, PI_BAD_I2C_ADDR,
PI_BAD_FLAGS, PI_NO_HANDLE, or PI_I2C_OPEN_FAILED.
For the SMBus commands the low level transactions are shown at the end
of the function description. The following abbreviations are used.
. .
S (1 bit) : Start bit
P (1 bit) : Stop bit
Rd/Wr (1 bit) : Read/Write bit. Rd equals 1, Wr equals 0.
A, NA (1 bit) : Accept and not accept bit.
Addr (7 bits): I2C 7 bit address.
Comm (8 bits): Command byte, a data byte which often selects a register.
Data (8 bits): A data byte.
Count (8 bits): A data byte containing the length of a block operation.
[..]: Data sent by the device.
. .
D*/
/*F*/
int i2cClose(unsigned handle);
/*D
This closes the I2C device associated with the handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE.
D*/
/*F*/
int i2cWriteQuick(unsigned handle, unsigned bit);
/*D
This sends a single bit (in the Rd/Wr bit) to the device associated
with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
bit: 0-1, the value to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
Quick command. SMBus 2.0 5.5.1
. .
S Addr Rd/Wr [A] P
. .
D*/
/*F*/
int i2cWriteByte(unsigned handle, unsigned bVal);
/*D
This sends a single byte to the device associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
bVal: 0-0xFF, the value to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
Send byte. SMBus 2.0 5.5.2
. .
S Addr Wr [A] Data [A] P
. .
D*/
/*F*/
int i2cReadByte(unsigned handle);
/*D
This reads a single byte from the device associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
. .
Returns the byte read (>=0) if OK, otherwise PI_BAD_HANDLE,
or PI_I2C_READ_FAILED.
Receive byte. SMBus 2.0 5.5.3
. .
S Addr Rd [A] [Data] NA P
. .
D*/
/*F*/
int i2cWriteByteData(unsigned handle, unsigned i2cReg, unsigned bVal);
/*D
This writes a single byte to the specified register of the device
associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to write
bVal: 0-0xFF, the value to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
Write byte. SMBus 2.0 5.5.4
. .
S Addr Wr [A] Comm [A] Data [A] P
. .
D*/
/*F*/
int i2cWriteWordData(unsigned handle, unsigned i2cReg, unsigned wVal);
/*D
This writes a single 16 bit word to the specified register of the device
associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to write
wVal: 0-0xFFFF, the value to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
Write word. SMBus 2.0 5.5.4
. .
S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A] P
. .
D*/
/*F*/
int i2cReadByteData(unsigned handle, unsigned i2cReg);
/*D
This reads a single byte from the specified register of the device
associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to read
. .
Returns the byte read (>=0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, or PI_I2C_READ_FAILED.
Read byte. SMBus 2.0 5.5.5
. .
S Addr Wr [A] Comm [A] S Addr Rd [A] [Data] NA P
. .
D*/
/*F*/
int i2cReadWordData(unsigned handle, unsigned i2cReg);
/*D
This reads a single 16 bit word from the specified register of the device
associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to read
. .
Returns the word read (>=0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, or PI_I2C_READ_FAILED.
Read word. SMBus 2.0 5.5.5
. .
S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
. .
D*/
/*F*/
int i2cProcessCall(unsigned handle, unsigned i2cReg, unsigned wVal);
/*D
This writes 16 bits of data to the specified register of the device
associated with handle and reads 16 bits of data in return.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to write/read
wVal: 0-0xFFFF, the value to write
. .
Returns the word read (>=0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, or PI_I2C_READ_FAILED.
Process call. SMBus 2.0 5.5.6
. .
S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A]
S Addr Rd [A] [DataLow] A [DataHigh] NA P
. .
D*/
/*F*/
int i2cWriteBlockData(
unsigned handle, unsigned i2cReg, char *buf, unsigned count);
/*D
This writes up to 32 bytes to the specified register of the device
associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to write
buf: an array with the data to send
count: 1-32, the number of bytes to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
Block write. SMBus 2.0 5.5.7
. .
S Addr Wr [A] Comm [A] Count [A] Data [A] Data [A] ... [A] Data [A] P
. .
D*/
/*F*/
int i2cReadBlockData(unsigned handle, unsigned i2cReg, char *buf);
/*D
This reads a block of up to 32 bytes from the specified register of
the device associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to read
buf: an array to receive the read data
. .
The amount of returned data is set by the device.
Returns the number of bytes read (>=0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, or PI_I2C_READ_FAILED.
Block read. SMBus 2.0 5.5.7
. .
S Addr Wr [A] Comm [A]
S Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P
. .
D*/
/*F*/
int i2cBlockProcessCall(
unsigned handle, unsigned i2cReg, char *buf, unsigned count);
/*D
This writes data bytes to the specified register of the device
associated with handle and reads a device specified number
of bytes of data in return.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to write/read
buf: an array with the data to send and to receive the read data
count: 1-32, the number of bytes to write
. .
Returns the number of bytes read (>=0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, or PI_I2C_READ_FAILED.
The SMBus 2.0 documentation states that a minimum of 1 byte may be
sent and a minimum of 1 byte may be received. The total number of
bytes sent/received must be 32 or less.
Block write-block read. SMBus 2.0 5.5.8
. .
S Addr Wr [A] Comm [A] Count [A] Data [A] ...
S Addr Rd [A] [Count] A [Data] ... A P
. .
D*/
/*F*/
int i2cReadI2CBlockData(
unsigned handle, unsigned i2cReg, char *buf, unsigned count);
/*D
This reads count bytes from the specified register of the device
associated with handle . The count may be 1-32.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to read
buf: an array to receive the read data
count: 1-32, the number of bytes to read
. .
Returns the number of bytes read (>0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, or PI_I2C_READ_FAILED.
. .
S Addr Wr [A] Comm [A]
S Addr Rd [A] [Data] A [Data] A ... A [Data] NA P
. .
D*/
/*F*/
int i2cWriteI2CBlockData(
unsigned handle, unsigned i2cReg, char *buf, unsigned count);
/*D
This writes 1 to 32 bytes to the specified register of the device
associated with handle.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
i2cReg: 0-255, the register to write
buf: the data to write
count: 1-32, the number of bytes to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
. .
S Addr Wr [A] Comm [A] Data [A] Data [A] ... [A] Data [A] P
. .
D*/
/*F*/
int i2cReadDevice(unsigned handle, char *buf, unsigned count);
/*D
This reads count bytes from the raw device into buf.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
buf: an array to receive the read data bytes
count: >0, the number of bytes to read
. .
Returns count (>0) if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_READ_FAILED.
D*/
/*F*/
int i2cWriteDevice(unsigned handle, char *buf, unsigned count);
/*D
This writes count bytes from buf to the raw device.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
buf: an array containing the data bytes to write
count: >0, the number of bytes to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_I2C_WRITE_FAILED.
D*/
/*F*/
void i2cSwitchCombined(int setting);
/*D
This sets the I2C (i2c-bcm2708) module "use combined transactions"
parameter on or off.
. .
setting: 0 to set the parameter off, non-zero to set it on
. .
NOTE: when the flag is on a write followed by a read to the same
slave address will use a repeated start (rather than a stop/start).
D*/
/*F*/
int i2cSegments(unsigned handle, pi_i2c_msg_t *segs, unsigned numSegs);
/*D
This function executes multiple I2C segments in one transaction by
calling the I2C_RDWR ioctl.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
segs: an array of I2C segments
numSegs: >0, the number of I2C segments
. .
Returns the number of segments if OK, otherwise PI_BAD_I2C_SEG.
D*/
/*F*/
int i2cZip(
unsigned handle,
char *inBuf,
unsigned inLen,
char *outBuf,
unsigned outLen);
/*D
This function executes a sequence of I2C operations. The
operations to be performed are specified by the contents of inBuf
which contains the concatenated command codes and associated data.
. .
handle: >=0, as returned by a call to [*i2cOpen*]
inBuf: pointer to the concatenated I2C commands, see below
inLen: size of command buffer
outBuf: pointer to buffer to hold returned data
outLen: size of output buffer
. .
Returns >= 0 if OK (the number of bytes read), otherwise
PI_BAD_HANDLE, PI_BAD_POINTER, PI_BAD_I2C_CMD, PI_BAD_I2C_RLEN.
PI_BAD_I2C_WLEN, or PI_BAD_I2C_SEG.
The following command codes are supported:
Name @ Cmd & Data @ Meaning
End @ 0 @ No more commands
Escape @ 1 @ Next P is two bytes
On @ 2 @ Switch combined flag on
Off @ 3 @ Switch combined flag off
Address @ 4 P @ Set I2C address to P
Flags @ 5 lsb msb @ Set I2C flags to lsb + (msb << 8)
Read @ 6 P @ Read P bytes of data
Write @ 7 P ... @ Write P bytes of data
The address, read, and write commands take a parameter P.
Normally P is one byte (0-255). If the command is preceded by
the Escape command then P is two bytes (0-65535, least significant
byte first).
The address defaults to that associated with the handle.
The flags default to 0. The address and flags maintain their
previous value until updated.
The returned I2C data is stored in consecutive locations of outBuf.
...
Set address 0x53, write 0x32, read 6 bytes
Set address 0x1E, write 0x03, read 6 bytes
Set address 0x68, write 0x1B, read 8 bytes
End
0x04 0x53 0x07 0x01 0x32 0x06 0x06
0x04 0x1E 0x07 0x01 0x03 0x06 0x06
0x04 0x68 0x07 0x01 0x1B 0x06 0x08
0x00
...
D*/
/*F*/
int bbI2COpen(unsigned SDA, unsigned SCL, unsigned baud);
/*D
This function selects a pair of gpios for bit banging I2C at a
specified baud rate.
Bit banging I2C allows for certain operations which are not possible
with the standard I2C driver.
o baud rates as low as 50
o repeated starts
o clock stretching
o I2C on any pair of spare gpios
. .
SDA: 0-31
SCL: 0-31
baud: 50-500000
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO, PI_BAD_I2C_BAUD, or
PI_GPIO_IN_USE.
NOTE:
The gpios used for SDA and SCL must have pull-ups to 3V3 connected. As
a guide the hardware pull-ups on pins 3 and 5 are 1k8 in value.
D*/
/*F*/
int bbI2CClose(unsigned SDA);
/*D
This function stops bit banging I2C on a pair of gpios previously
opened with [*bbI2COpen*].
. .
SDA: 0-31, the SDA gpio used in a prior call to [*bbI2COpen*]
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO, or PI_NOT_I2C_GPIO.
D*/
/*F*/
int bbI2CZip(
unsigned SDA,
char *inBuf,
unsigned inLen,
char *outBuf,
unsigned outLen);
/*D
This function executes a sequence of bit banged I2C operations. The
operations to be performed are specified by the contents of inBuf
which contains the concatenated command codes and associated data.
. .
SDA: 0-31 (as used in a prior call to [*bbI2COpen*])
inBuf: pointer to the concatenated I2C commands, see below
inLen: size of command buffer
outBuf: pointer to buffer to hold returned data
outLen: size of output buffer
. .
Returns >= 0 if OK (the number of bytes read), otherwise
PI_BAD_USER_GPIO, PI_NOT_I2C_GPIO, PI_BAD_POINTER,
PI_BAD_I2C_CMD, PI_BAD_I2C_RLEN, PI_BAD_I2C_WLEN,
PI_I2C_READ_FAILED, or PI_I2C_WRITE_FAILED.
The following command codes are supported:
Name @ Cmd & Data @ Meaning
End @ 0 @ No more commands
Escape @ 1 @ Next P is two bytes
Start @ 2 @ Start condition
Stop @ 3 @ Stop condition
Address @ 4 P @ Set I2C address to P
Flags @ 5 lsb msb @ Set I2C flags to lsb + (msb << 8)
Read @ 6 P @ Read P bytes of data
Write @ 7 P ... @ Write P bytes of data
The address, read, and write commands take a parameter P.
Normally P is one byte (0-255). If the command is preceded by
the Escape command then P is two bytes (0-65535, least significant
byte first).
The address and flags default to 0. The address and flags maintain
their previous value until updated.
No flags are currently defined.
The returned I2C data is stored in consecutive locations of outBuf.
...
Set address 0x53
start, write 0x32, (re)start, read 6 bytes, stop
Set address 0x1E
start, write 0x03, (re)start, read 6 bytes, stop
Set address 0x68
start, write 0x1B, (re)start, read 8 bytes, stop
End
0x04 0x53
0x02 0x07 0x01 0x32 0x02 0x06 0x06 0x03
0x04 0x1E
0x02 0x07 0x01 0x03 0x02 0x06 0x06 0x03
0x04 0x68
0x02 0x07 0x01 0x1B 0x02 0x06 0x08 0x03
0x00
...
D*/
/*F*/
int spiOpen(unsigned spiChan, unsigned baud, unsigned spiFlags);
/*D
This function returns a handle for the SPI device on the channel.
Data will be transferred at baud bits per second. The flags may
be used to modify the default behaviour of 4-wire operation, mode 0,
active low chip select.
An auxiliary SPI device is available on the A+/B+/Pi2 and may be
selected by setting the A bit in the flags. The auxiliary
device has 3 chip selects and a selectable word size in bits.
. .
spiChan: 0-1 (0-2 for A+/B+/Pi2 auxiliary device)
baud: 32K-125M (values above 30M are unlikely to work)
spiFlags: see below
. .
Returns a handle (>=0) if OK, otherwise PI_BAD_SPI_CHANNEL,
PI_BAD_SPI_SPEED, PI_BAD_FLAGS, PI_NO_AUX_SPI, or PI_SPI_OPEN_FAILED.
spiFlags consists of the least significant 22 bits.
. .
21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
b b b b b b R T n n n n W A u2 u1 u0 p2 p1 p0 m m
. .
mm defines the SPI mode.
Warning: modes 1 and 3 do not appear to work on the auxiliary device.
. .
Mode POL PHA
0 0 0
1 0 1
2 1 0
3 1 1
. .
px is 0 if CEx is active low (default) and 1 for active high.
ux is 0 if the CEx gpio is reserved for SPI (default) and 1 otherwise.
A is 0 for the standard SPI device, 1 for the auxiliary SPI. The
auxiliary device is only present on the A+/B+/Pi2.
W is 0 if the device is not 3-wire, 1 if the device is 3-wire. Standard
SPI device only.
nnnn defines the number of bytes (0-15) to write before switching
the MOSI line to MISO to read data. This field is ignored
if W is not set. Standard SPI device only.
T is 1 if the least significant bit is transmitted on MOSI first, the
default (0) shifts the most significant bit out first. Auxiliary SPI
device only.
R is 1 if the least significant bit is received on MISO first, the
default (0) receives the most significant bit first. Auxiliary SPI
device only.
bbbbbb defines the word size in bits (0-32). The default (0)
sets 8 bits per word. Auxiliary SPI device only.
The other bits in flags should be set to zero.
D*/
/*F*/
int spiClose(unsigned handle);
/*D
This functions closes the SPI device identified by the handle.
. .
handle: >=0, as returned by a call to [*spiOpen*]
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE.
D*/
/*F*/
int spiRead(unsigned handle, char *buf, unsigned count);
/*D
This function reads count bytes of data from the SPI
device associated with the handle.
. .
handle: >=0, as returned by a call to [*spiOpen*]
buf: an array to receive the read data bytes
count: the number of bytes to read
. .
Returns the number of bytes transferred if OK, otherwise
PI_BAD_HANDLE, PI_BAD_SPI_COUNT, or PI_SPI_XFER_FAILED.
D*/
/*F*/
int spiWrite(unsigned handle, char *buf, unsigned count);
/*D
This function writes count bytes of data from buf to the SPI
device associated with the handle.
. .
handle: >=0, as returned by a call to [*spiOpen*]
buf: the data bytes to write
count: the number of bytes to write
. .
Returns the number of bytes transferred if OK, otherwise
PI_BAD_HANDLE, PI_BAD_SPI_COUNT, or PI_SPI_XFER_FAILED.
D*/
/*F*/
int spiXfer(unsigned handle, char *txBuf, char *rxBuf, unsigned count);
/*D
This function transfers count bytes of data from txBuf to the SPI
device associated with the handle. Simultaneously count bytes of
data are read from the device and placed in rxBuf.
. .
handle: >=0, as returned by a call to [*spiOpen*]
txBuf: the data bytes to write
rxBuf: the received data bytes
count: the number of bytes to transfer
. .
Returns the number of bytes transferred if OK, otherwise
PI_BAD_HANDLE, PI_BAD_SPI_COUNT, or PI_SPI_XFER_FAILED.
D*/
/*F*/
int serOpen(char *sertty, unsigned baud, unsigned serFlags);
/*D
This function opens a serial device at a specified baud rate
with specified flags.
. .
sertty: the serial device to open, /dev/tty*
baud: the baud rate in bits per second, see below
serFlags: 0
. .
Returns a handle (>=0) if OK, otherwise PI_NO_HANDLE, or
PI_SER_OPEN_FAILED.
The baud rate must be one of 50, 75, 110, 134, 150,
200, 300, 600, 1200, 1800, 2400, 4800, 9500, 19200,
38400, 57600, 115200, or 230400.
No flags are currently defined. This parameter should be set to zero.
D*/
/*F*/
int serClose(unsigned handle);
/*D
This function closes the serial device associated with handle.
. .
handle: >=0, as returned by a call to [*serOpen*]
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE.
D*/
/*F*/
int serWriteByte(unsigned handle, unsigned bVal);
/*D
This function writes bVal to the serial port associated with handle.
. .
handle: >=0, as returned by a call to [*serOpen*]
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_SER_WRITE_FAILED.
D*/
/*F*/
int serReadByte(unsigned handle);
/*D
This function reads a byte from the serial port associated with handle.
. .
handle: >=0, as returned by a call to [*serOpen*]
. .
Returns the read byte (>=0) if OK, otherwise PI_BAD_HANDLE,
PI_SER_READ_NO_DATA, or PI_SER_READ_FAILED.
D*/
/*F*/
int serWrite(unsigned handle, char *buf, unsigned count);
/*D
This function writes count bytes from buf to the the serial port
associated with handle.
. .
handle: >=0, as returned by a call to [*serOpen*]
buf: the array of bytes to write
count: the number of bytes to write
. .
Returns 0 if OK, otherwise PI_BAD_HANDLE, PI_BAD_PARAM, or
PI_SER_WRITE_FAILED.
D*/
/*F*/
int serRead(unsigned handle, char *buf, unsigned count);
/*D
This function reads up count bytes from the the serial port
associated with handle and writes them to buf.
. .
handle: >=0, as returned by a call to serial_open
buf: an array to receive the read data
count: the maximum number of bytes to read
. .
Returns the number of bytes read (>0) if OK, otherwise PI_BAD_HANDLE,
PI_BAD_PARAM, PI_SER_READ_NO_DATA, or PI_SER_WRITE_FAILED.
D*/
/*F*/
int serDataAvailable(unsigned handle);
/*D
This function returns the number of bytes available
to be read from the device associated with handle.
. .
handle: >=0, as returned by a call to [*serOpen*]
. .
Returns the number of bytes of data available (>=0) if OK,
otherwise PI_BAD_HANDLE.
D*/
/*F*/
int gpioTrigger(unsigned user_gpio, unsigned pulseLen, unsigned level);
/*D
This function sends a trigger pulse to a gpio. The gpio is set to
level for pulseLen microseconds and then reset to not level.
. .
user_gpio: 0-31
pulseLen: 1-100
level: 0,1
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO, PI_BAD_LEVEL,
or PI_BAD_PULSELEN.
D*/
/*F*/
int gpioSetWatchdog(unsigned user_gpio, unsigned timeout);
/*D
Sets a watchdog for a gpio.
. .
user_gpio: 0-31
timeout: 0-60000
. .
Returns 0 if OK, otherwise PI_BAD_USER_GPIO or PI_BAD_WDOG_TIMEOUT.
The watchdog is nominally in milliseconds.
One watchdog may be registered per gpio.
The watchdog may be cancelled by setting timeout to 0.
If no level change has been detected for the gpio for timeout
milliseconds:-
1) any registered alert function for the gpio is called with
the level set to PI_TIMEOUT.
2) any notification for the gpio has a report written to the
fifo with the flags set to indicate a watchdog timeout.
...
void aFunction(int gpio, int level, uint32_t tick)
{
printf("gpio %d became %d at %d\n", gpio, level, tick);
}
// call aFunction whenever gpio 4 changes state
gpioSetAlertFunc(4, aFunction);
// or approximately every 5 millis
gpioSetWatchdog(4, 5);
...
D*/
/*F*/
int gpioSetGetSamplesFunc(gpioGetSamplesFunc_t f, uint32_t bits);
/*D
Registers a function to be called (a callback) every millisecond
with the latest gpio samples.
. .
f: the function to call
bits: the gpios of interest
. .
Returns 0 if OK.
The function is passed a pointer to the samples (an array of
[*gpioSample_t*]), and the number of samples.
Only one function can be registered.
The callback may be cancelled by passing NULL as the function.
The samples returned will be the union of bits, plus any active alerts,
plus any active notifications.
e.g. if there are alerts for gpios 7, 8, and 9, notifications for gpios
8, 10, 23, 24, and bits is (1<<23)|(1<<17) then samples for gpios
7, 8, 9, 10, 17, 23, and 24 will be reported.
D*/
/*F*/
int gpioSetGetSamplesFuncEx(
gpioGetSamplesFuncEx_t f, uint32_t bits, void *userdata);
/*D
Registers a function to be called (a callback) every millisecond
with the latest gpio samples.
. .
f: the function to call
bits: the gpios of interest
userdata: a pointer to arbitrary user data
. .
Returns 0 if OK.
The function is passed a pointer to the samples (an array of
[*gpioSample_t*]), the number of samples, and the userdata pointer.
Only one of [*gpioGetSamplesFunc*] or [*gpioGetSamplesFuncEx*] can be
registered.
See [*gpioSetGetSamplesFunc*] for further details.
D*/
/*F*/
int gpioSetTimerFunc(unsigned timer, unsigned millis, gpioTimerFunc_t f);
/*D
Registers a function to be called (a callback) every millis milliseconds.
. .
timer: 0-9
millis: 10-60000
f: the function to call
. .
Returns 0 if OK, otherwise PI_BAD_TIMER, PI_BAD_MS, or PI_TIMER_FAILED.
10 timers are supported numbered 0 to 9.
One function may be registered per timer.
The timer may be cancelled by passing NULL as the function.
...
void bFunction(void)
{
printf("two seconds have elapsed\n");
}
// call bFunction every 2000 milliseconds
gpioSetTimerFunc(0, 2000, bFunction);
...
D*/
/*F*/
int gpioSetTimerFuncEx(
unsigned timer, unsigned millis, gpioTimerFuncEx_t f, void *userdata);
/*D
Registers a function to be called (a callback) every millis milliseconds.
. .
timer: 0-9.
millis: 10-60000
f: the function to call
userdata: a pointer to arbitrary user data
. .
Returns 0 if OK, otherwise PI_BAD_TIMER, PI_BAD_MS, or PI_TIMER_FAILED.
The function is passed the userdata pointer.
Only one of [*gpioSetTimerFunc*] or [*gpioSetTimerFuncEx*] can be
registered per timer.
See [*gpioSetTimerFunc*] for further details.
D*/
/*F*/
pthread_t *gpioStartThread(gpioThreadFunc_t f, void *arg);
/*D
Starts a new thread of execution with f as the main routine.
. .
f: the main function for the new thread
arg: a pointer to arbitrary user data
. .
Returns a pointer to pthread_t if OK, otherwise NULL.
The function is passed the single argument arg.
The thread can be cancelled by passing the pointer to pthread_t to
[*gpioStopThread*].
...
#include
#include
void *myfunc(void *arg)
{
while (1)
{
printf("%s\n", arg);
sleep(1);
}
}
int main(int argc, char *argv[])
{
pthread_t *p1, *p2, *p3;
if (gpioInitialise() < 0) return 1;
p1 = gpioStartThread(myfunc, "thread 1"); sleep(3);
p2 = gpioStartThread(myfunc, "thread 2"); sleep(3);
p3 = gpioStartThread(myfunc, "thread 3"); sleep(3);
gpioStopThread(p3); sleep(3);
gpioStopThread(p2); sleep(3);
gpioStopThread(p1); sleep(3);
gpioTerminate();
}
...
D*/
/*F*/
void gpioStopThread(pthread_t *pth);
/*D
Cancels the thread pointed at by pth.
. .
pth: a thread pointer returned by [*gpioStartThread*]
. .
No value is returned.
The thread to be stopped should have been started with [*gpioStartThread*].
D*/
/*F*/
int gpioStoreScript(char *script);
/*D
This function stores a null terminated script for later execution.
. .
script: the text of the script
. .
The function returns a script id if the script is valid,
otherwise PI_BAD_SCRIPT.
D*/
/*F*/
int gpioRunScript(unsigned script_id, unsigned numPar, uint32_t *param);
/*D
This function runs a stored script.
. .
script_id: >=0, as returned by [*gpioStoreScript*]
numPar: 0-10, the number of parameters
param: an array of parameters
. .
The function returns 0 if OK, otherwise PI_BAD_SCRIPT_ID, or
PI_TOO_MANY_PARAM.
param is an array of up to 10 parameters which may be referenced in
the script as p0 to p9.
D*/
/*F*/
int gpioScriptStatus(unsigned script_id, uint32_t *param);
/*D
This function returns the run status of a stored script as well as
the current values of parameters 0 to 9.
. .
script_id: >=0, as returned by [*gpioStoreScript*]
param: an array to hold the returned 10 parameters
. .
The function returns greater than or equal to 0 if OK,
otherwise PI_BAD_SCRIPT_ID.
The run status may be
. .
PI_SCRIPT_INITING
PI_SCRIPT_HALTED
PI_SCRIPT_RUNNING
PI_SCRIPT_WAITING
PI_SCRIPT_FAILED
. .
The current value of script parameters 0 to 9 are returned in param.
D*/
/*F*/
int gpioStopScript(unsigned script_id);
/*D
This function stops a running script.
. .
script_id: >=0, as returned by [*gpioStoreScript*]
. .
The function returns 0 if OK, otherwise PI_BAD_SCRIPT_ID.
D*/
/*F*/
int gpioDeleteScript(unsigned script_id);
/*D
This function deletes a stored script.
. .
script_id: >=0, as returned by [*gpioStoreScript*]
. .
The function returns 0 if OK, otherwise PI_BAD_SCRIPT_ID.
D*/
/*F*/
int gpioSetSignalFunc(unsigned signum, gpioSignalFunc_t f);
/*D
Registers a function to be called (a callback) when a signal occurs.
. .
signum: 0-63
f: the callback function
. .
Returns 0 if OK, otherwise PI_BAD_SIGNUM.
The function is passed the signal number.
One function may be registered per signal.
The callback may be cancelled by passing NULL.
By default all signals are treated as fatal and cause the library
to call gpioTerminate and then exit.
D*/
/*F*/
int gpioSetSignalFuncEx(
unsigned signum, gpioSignalFuncEx_t f, void *userdata);
/*D
Registers a function to be called (a callback) when a signal occurs.
. .
signum: 0-63
f: the callback function
userdata: a pointer to arbitrary user data
. .
Returns 0 if OK, otherwise PI_BAD_SIGNUM.
The function is passed the signal number and the userdata pointer.
Only one of gpioSetSignalFunc or gpioSetSignalFuncEx can be
registered per signal.
See gpioSetSignalFunc for further details.
D*/
/*F*/
uint32_t gpioRead_Bits_0_31(void);
/*D
Returns the current level of gpios 0-31.
D*/
/*F*/
uint32_t gpioRead_Bits_32_53(void);
/*D
Returns the current level of gpios 32-53.
D*/
/*F*/
int gpioWrite_Bits_0_31_Clear(uint32_t bits);
/*D
Clears gpios 0-31 if the corresponding bit in bits is set.
. .
bits: a bit mask of gpios to clear
. .
Returns 0 if OK.
...
// To clear (set to 0) gpios 4, 7, and 15
gpioWrite_Bits_0_31_Clear( (1<<4) | (1<<7) | (1<<15) );
...
D*/
/*F*/
int gpioWrite_Bits_32_53_Clear(uint32_t bits);
/*D
Clears gpios 32-53 if the corresponding bit (0-21) in bits is set.
. .
bits: a bit mask of gpios to clear
. .
Returns 0 if OK.
D*/
/*F*/
int gpioWrite_Bits_0_31_Set(uint32_t bits);
/*D
Sets gpios 0-31 if the corresponding bit in bits is set.
. .
bits: a bit mask of gpios to set
. .
Returns 0 if OK.
D*/
/*F*/
int gpioWrite_Bits_32_53_Set(uint32_t bits);
/*D
Sets gpios 32-53 if the corresponding bit (0-21) in bits is set.
. .
bits: a bit mask of gpios to set
. .
Returns 0 if OK.
...
// To set (set to 1) gpios 32, 40, and 53
gpioWrite_Bits_32_53_Set((1<<(32-32)) | (1<<(40-32)) | (1<<(53-32)));
...
D*/
/*F*/
int gpioHardwareClock(unsigned gpio, unsigned clkfreq);
/*D
Starts a hardware clock on a gpio at the specified frequency.
Frequencies above 30MHz are unlikely to work.
. .
gpio: see description
clkfreq: 0 (off) or 4689-250000000 (250M)
. .
Returns 0 if OK, otherwise PI_BAD_GPIO, PI_NOT_HCLK_GPIO,
PI_BAD_HCLK_FREQ,or PI_BAD_HCLK_PASS.
The same clock is available on multiple gpios. The latest
frequency setting will be used by all gpios which share a clock.
The gpio must be one of the following.
. .
4 clock 0 All models
5 clock 1 A+/B+/Pi2 and compute module only (reserved for system use)
6 clock 2 A+/B+/Pi2 and compute module only
20 clock 0 A+/B+/Pi2 and compute module only
21 clock 1 All models but Rev.2 B (reserved for system use)
32 clock 0 Compute module only
34 clock 0 Compute module only
42 clock 1 Compute module only (reserved for system use)
43 clock 2 Compute module only
44 clock 1 Compute module only (reserved for system use)
. .
Access to clock 1 is protected by a password as its use will likely
crash the Pi. The password is given by or'ing 0x5A000000 with the
gpio number.
D*/
/*F*/
int gpioHardwarePWM(unsigned gpio, unsigned PWMfreq, unsigned PWMduty);
/*D
Starts hardware PWM on a gpio at the specified frequency and dutycycle.
Frequencies above 30MHz are unlikely to work.
NOTE: Any waveform started by [*gpioWaveTxSend*], or
[*gpioWaveChain*] will be cancelled.
This function is only valid if the pigpio main clock is PCM. The
main clock defaults to PCM but may be overridden by a call to
[*gpioCfgClock*].
. .
gpio: see description
PWMfreq: 0 (off) or 1-125000000 (125M)
PWMduty: 0 (off) to 1000000 (1M)(fully on)
. .
Returns 0 if OK, otherwise PI_BAD_GPIO, PI_NOT_HPWM_GPIO,
PI_BAD_HPWM_DUTY, PI_BAD_HPWM_FREQ, or PI_HPWM_ILLEGAL.
The same PWM channel is available on multiple gpios. The latest
frequency and dutycycle setting will be used by all gpios which
share a PWM channel.
The gpio must be one of the following.
. .
12 PWM channel 0 A+/B+/Pi2 and compute module only
13 PWM channel 1 A+/B+/Pi2 and compute module only
18 PWM channel 0 All models
19 PWM channel 1 A+/B+/Pi2 and compute module only
40 PWM channel 0 Compute module only
41 PWM channel 1 Compute module only
45 PWM channel 1 Compute module only
52 PWM channel 0 Compute module only
53 PWM channel 1 Compute module only
. .
D*/
/*F*/
int gpioTime(unsigned timetype, int *seconds, int *micros);
/*D
Updates the seconds and micros variables with the current time.
. .
timetype: 0 (relative), 1 (absolute)
seconds: a pointer to an int to hold seconds
micros: a pointer to an int to hold microseconds
. .
Returns 0 if OK, otherwise PI_BAD_TIMETYPE.
If timetype is PI_TIME_ABSOLUTE updates seconds and micros with the
number of seconds and microseconds since the epoch (1st January 1970).
If timetype is PI_TIME_RELATIVE updates seconds and micros with the
number of seconds and microseconds since the library was initialised.
...
int secs, mics;
// print the number of seconds since the library was started
gpioTime(PI_TIME_RELATIVE, &secs, &mics);
printf("library started %d.%03d seconds ago\n", secs, mics/1000);
...
D*/
/*F*/
int gpioSleep(unsigned timetype, int seconds, int micros);
/*D
Sleeps for the number of seconds and microseconds specified by seconds
and micros.
. .
timetype: 0 (relative), 1 (absolute)
seconds: seconds to sleep
micros: microseconds to sleep
. .
Returns 0 if OK, otherwise PI_BAD_TIMETYPE, PI_BAD_SECONDS,
or PI_BAD_MICROS.
If timetype is PI_TIME_ABSOLUTE the sleep ends when the number of seconds
and microseconds since the epoch (1st January 1970) has elapsed. System
clock changes are taken into account.
If timetype is PI_TIME_RELATIVE the sleep is for the specified number
of seconds and microseconds. System clock changes do not effect the
sleep length.
For short delays (say, 50 microseonds or less) use [*gpioDelay*].
...
gpioSleep(PI_TIME_RELATIVE, 2, 500000); // sleep for 2.5 seconds
gpioSleep(PI_TIME_RELATIVE, 0, 100000); // sleep for 0.1 seconds
gpioSleep(PI_TIME_RELATIVE, 60, 0); // sleep for one minute
...
D*/
/*F*/
uint32_t gpioDelay(uint32_t micros);
/*D
Delays for at least the number of microseconds specified by micros.
. .
micros: the number of microseconds to sleep
. .
Returns the actual length of the delay in microseconds.
Delays of 100 microseconds or less use busy waits.
D*/
/*F*/
uint32_t gpioTick(void);
/*D
Returns the current system tick.
Tick is the number of microseconds since system boot.
As tick is an unsigned 32 bit quantity it wraps around after
2^32 microseconds, which is approximately 1 hour 12 minutes.
You don't need to worry about the wrap around as long as you
take a tick (uint32_t) from another tick, i.e. the following
code will always provide the correct difference.
...
uint32_t startTick, endTick;
int diffTick;
startTick = gpioTick();
// do some processing
endTick = gpioTick();
diffTick = endTick - startTick;
printf("some processing took %d microseconds\n", diffTick);
...
D*/
/*F*/
unsigned gpioHardwareRevision(void);
/*D
Returns the hardware revision.
If the hardware revision can not be found or is not a valid hexadecimal
number the function returns 0.
The hardware revision is the last few characters on the Revision line of
/proc/cpuinfo.
The revision number can be used to determine the assignment of gpios
to pins (see [*gpio*]).
There are at least three types of board.
Type 1 boards have hardware revision numbers of 2 and 3.
Type 2 boards have hardware revision numbers of 4, 5, 6, and 15.
Type 3 boards have hardware revision numbers of 16 or greater.
for "Revision : 0002" the function returns 2.
for "Revision : 000f" the function returns 15.
for "Revision : 000g" the function returns 0.
D*/
/*F*/
unsigned gpioVersion(void);
/*D
Returns the pigpio version.
D*/
/*F*/
int gpioCfgBufferSize(unsigned cfgMillis);
/*D
Configures pigpio to buffer cfgMillis milliseconds of gpio samples.
. .
cfgMillis: 100-10000
. .
The default setting is 120 milliseconds.
The intention is to allow for bursts of data and protection against
other processes hogging cpu time.
I haven't seen a process locked out for more than 100 milliseconds.
Making the buffer bigger uses a LOT of memory at the more frequent
sampling rates as shown in the following table in MBs.
. .
buffer milliseconds
120 250 500 1sec 2sec 4sec 8sec
1 16 31 55 107 --- --- ---
2 10 18 31 55 107 --- ---
sample 4 8 12 18 31 55 107 ---
rate 5 8 10 14 24 45 87 ---
(us) 8 6 8 12 18 31 55 107
10 6 8 10 14 24 45 87
. .
D*/
/*F*/
int gpioCfgClock(
unsigned cfgMicros, unsigned cfgPeripheral, unsigned cfgSource);
/*D
Configures pigpio to use a particular sample rate timed by a specified
peripheral.
. .
cfgMicros: 1, 2, 4, 5, 8, 10
cfgPeripheral: 0 (PWM), 1 (PCM)
cfgSource: deprecated, value is ignored
. .
The timings are provided by the specified peripheral (PWM or PCM).
The default setting is 5 microseconds using the PCM peripheral.
The approximate CPU percentage used for each sample rate is:
. .
sample cpu
rate %
1 25
2 16
4 11
5 10
8 15
10 14
. .
A sample rate of 5 microseconds seeems to be the sweet spot.
D*/
/*F*/
int gpioCfgDMAchannel(unsigned DMAchannel); /* DEPRECATED */
/*D
Configures pigpio to use the specified DMA channel.
. .
DMAchannel: 0-14
. .
The default setting is to use channel 14.
D*/
/*F*/
int gpioCfgDMAchannels(
unsigned primaryChannel, unsigned secondaryChannel);
/*D
Configures pigpio to use the specified DMA channels.
. .
primaryChannel: 0-14
secondaryChannel: 0-6
. .
The default setting is to use channel 14 for the primary channel and
channel 5 for the secondary channel.
D*/
/*F*/
int gpioCfgPermissions(uint64_t updateMask);
/*D
Configures pigpio to only allow updates (writes or mode changes) for the
gpios specified by the mask.
. .
updateMask: bit (1<=0
arg2: >=0
argx: extra (byte) arguments
argc: number of extra arguments
. .
Returns >= 0 if OK, less than 0 indicates a user defined error.
D*/
/*F*/
int gpioCustom2(unsigned arg1, char *argx, unsigned argc,
char *retBuf, unsigned retMax);
/*D
This function is available for user customisation.
It differs from gpioCustom1 in that it returns an array of bytes
rather than just an integer.
The returned value is an integer indicating the number of returned bytes.
. .
arg1: >=0
argx: extra (byte) arguments
argc: number of extra arguments
retBuf: buffer for returned bytes
retMax: maximum number of bytes to return
. .
Returns >= 0 if OK, less than 0 indicates a user defined error.
The number of returned bytes must be retMax or less.
D*/
/*F*/
int rawWaveAddSPI(
rawSPI_t *spi,
unsigned offset,
unsigned spiSS,
char *buf,
unsigned spiTxBits,
unsigned spiBitFirst,
unsigned spiBitLast,
unsigned spiBits);
/*D
This function adds a waveform representing SPI data to the
existing waveform (if any).
. .
spi: a pointer to a spi object
offset: microseconds from the start of the waveform
spiSS: the slave select gpio
buf: the bits to transmit, most significant bit first
spiTxBits: the number of bits to write
spiBitFirst: the first bit to read
spiBitLast: the last bit to read
spiBits: the number of bits to transfer
. .
Returns the new total number of pulses in the current waveform if OK,
otherwise PI_BAD_USER_GPIO, PI_BAD_SER_OFFSET, or PI_TOO_MANY_PULSES.
Not intended for general use.
D*/
/*F*/
int rawWaveAddGeneric(unsigned numPulses, rawWave_t *pulses);
/*D
This function adds a number of pulses to the current waveform.
. .
numPulses: the number of pulses
pulses: the array containing the pulses
. .
Returns the new total number of pulses in the current waveform if OK,
otherwise PI_TOO_MANY_PULSES.
The advantage of this function over gpioWaveAddGeneric is that it
allows the setting of the flags field.
The pulses are interleaved in time order within the existing waveform
(if any).
Merging allows the waveform to be built in parts, that is the settings
for gpio#1 can be added, and then gpio#2 etc.
If the added waveform is intended to start after or within the existing
waveform then the first pulse should consist of a delay.
Not intended for general use.
D*/
/*F*/
unsigned rawWaveCB(void);
/*D
Returns the number of the cb being currently output.
Not intended for general use.
D*/
/*F*/
rawCbs_t *rawWaveCBAdr(int cbNum);
/*D
Return the Linux address of contol block cbNum.
. .
cbNum: the cb of interest
. .
Not intended for general use.
D*/
/*F*/
uint32_t rawWaveGetOut(int pos);
/*D
Gets the wave output parameter stored at pos.
. .
pos: the position of interest.
. .
Not intended for general use.
D*/
/*F*/
void rawWaveSetOut(int pos, uint32_t lVal);
/*D
Sets the wave output parameter stored at pos to value.
. .
pos: the position of interest
lVal: the value to write
. .
Not intended for general use.
D*/
/*F*/
uint32_t rawWaveGetIn(int pos);
/*D
Gets the wave input value parameter stored at pos.
. .
pos: the position of interest
. .
Not intended for general use.
D*/
/*F*/
void rawWaveSetIn(int pos, uint32_t lVal);
/*D
Sets the wave input value stored at pos to value.
. .
pos: the position of interest
lVal: the value to write
. .
Not intended for general use.
D*/
/*F*/
rawWaveInfo_t rawWaveInfo(int wave_id);
/*D
Gets details about the wave with id wave_id.
. .
wave_id: the wave of interest
. .
Not intended for general use.
D*/
/*F*/
int getBitInBytes(int bitPos, char *buf, int numBits);
/*D
Returns the value of the bit bitPos bits from the start of buf. Returns
0 if bitPos is greater than or equal to numBits.
. .
bitPos: bit index from the start of buf
buf: array of bits
numBits: number of valid bits in buf
. .
D*/
/*F*/
void putBitInBytes(int bitPos, char *buf, int bit);
/*D
Sets the bit bitPos bits from the start of buf to bit.
. .
bitPos: bit index from the start of buf
buf: array of bits
bit: 0-1, value to set
. .
D*/
/*F*/
double time_time(void);
/*D
Return the current time in seconds since the Epoch.
D*/
/*F*/
void time_sleep(double seconds);
/*D
Delay execution for a given number of seconds
. .
seconds: the number of seconds to sleep
. .
D*/
/*F*/
void rawDumpWave(void);
/*D
Used to print a readable version of the current waveform to stderr.
Not intended for general use.
D*/
/*F*/
void rawDumpScript(unsigned script_id);
/*D
Used to print a readable version of a script to stderr.
. .
script_id: >=0, a script_id returned by [*gpioStoreScript*]
. .
Not intended for general use.
D*/
#ifdef __cplusplus
}
#endif
/*PARAMS
*arg::
A pointer to a void object passed to a thread started by gpioStartThread.
arg1::
An unsigned argument passed to a user customised function. Its
meaning is defined by the customiser.
arg2::
An unsigned argument passed to a user customised function. Its
meaning is defined by the customiser.
argc::
The count of bytes passed to a user customised function.
*argx::
A pointer to an array of bytes passed to a user customised function.
Its meaning and content is defined by the customiser.
baud::
The speed of serial communication (I2C, SPI, serial link, waves) in
bits per second.
bit::
A value of 0 or 1.
bitPos::
A bit position within a byte or word. The least significant bit is
position 0.
bits::
A value used to select gpios. If bit n of bits is set then gpio n is
selected.
A convenient way to set bit n is to or in (1<= 0.
updateMask::
A 64 bit mask indicating which gpios may be written to by the user.
If gpio#n may be written then bit (1< 3
#define PI_BAD_CHANNEL -27 // DMA channel not 0-14
#define PI_BAD_PRIM_CHANNEL -27 // DMA primary channel not 0-14
#define PI_BAD_SOCKET_PORT -28 // socket port not 1024-32000
#define PI_BAD_FIFO_COMMAND -29 // unrecognized fifo command
#define PI_BAD_SECO_CHANNEL -30 // DMA secondary channel not 0-6
#define PI_NOT_INITIALISED -31 // function called before gpioInitialise
#define PI_INITIALISED -32 // function called after gpioInitialise
#define PI_BAD_WAVE_MODE -33 // waveform mode not 0-1
#define PI_BAD_CFG_INTERNAL -34 // bad parameter in gpioCfgInternals call
#define PI_BAD_WAVE_BAUD -35 // baud rate not 50-250K(RX)/50-1M(TX)
#define PI_TOO_MANY_PULSES -36 // waveform has too many pulses
#define PI_TOO_MANY_CHARS -37 // waveform has too many chars
#define PI_NOT_SERIAL_GPIO -38 // no bit bang serial read in progress on gpio
#define PI_BAD_SERIAL_STRUC -39 // bad (null) serial structure parameter
#define PI_BAD_SERIAL_BUF -40 // bad (null) serial buf parameter
#define PI_NOT_PERMITTED -41 // gpio operation not permitted
#define PI_SOME_PERMITTED -42 // one or more gpios not permitted
#define PI_BAD_WVSC_COMMND -43 // bad WVSC subcommand
#define PI_BAD_WVSM_COMMND -44 // bad WVSM subcommand
#define PI_BAD_WVSP_COMMND -45 // bad WVSP subcommand
#define PI_BAD_PULSELEN -46 // trigger pulse length not 1-100
#define PI_BAD_SCRIPT -47 // invalid script
#define PI_BAD_SCRIPT_ID -48 // unknown script id
#define PI_BAD_SER_OFFSET -49 // add serial data offset > 30 minutes
#define PI_GPIO_IN_USE -50 // gpio already in use
#define PI_BAD_SERIAL_COUNT -51 // must read at least a byte at a time
#define PI_BAD_PARAM_NUM -52 // script parameter id not 0-9
#define PI_DUP_TAG -53 // script has duplicate tag
#define PI_TOO_MANY_TAGS -54 // script has too many tags
#define PI_BAD_SCRIPT_CMD -55 // illegal script command
#define PI_BAD_VAR_NUM -56 // script variable id not 0-149
#define PI_NO_SCRIPT_ROOM -57 // no more room for scripts
#define PI_NO_MEMORY -58 // can't allocate temporary memory
#define PI_SOCK_READ_FAILED -59 // socket read failed
#define PI_SOCK_WRIT_FAILED -60 // socket write failed
#define PI_TOO_MANY_PARAM -61 // too many script parameters (> 10)
#define PI_NOT_HALTED -62 // script already running or failed
#define PI_BAD_TAG -63 // script has unresolved tag
#define PI_BAD_MICS_DELAY -64 // bad MICS delay (too large)
#define PI_BAD_MILS_DELAY -65 // bad MILS delay (too large)
#define PI_BAD_WAVE_ID -66 // non existent wave id
#define PI_TOO_MANY_CBS -67 // No more CBs for waveform
#define PI_TOO_MANY_OOL -68 // No more OOL for waveform
#define PI_EMPTY_WAVEFORM -69 // attempt to create an empty waveform
#define PI_NO_WAVEFORM_ID -70 // no more waveforms
#define PI_I2C_OPEN_FAILED -71 // can't open I2C device
#define PI_SER_OPEN_FAILED -72 // can't open serial device
#define PI_SPI_OPEN_FAILED -73 // can't open SPI device
#define PI_BAD_I2C_BUS -74 // bad I2C bus
#define PI_BAD_I2C_ADDR -75 // bad I2C address
#define PI_BAD_SPI_CHANNEL -76 // bad SPI channel
#define PI_BAD_FLAGS -77 // bad i2c/spi/ser open flags
#define PI_BAD_SPI_SPEED -78 // bad SPI speed
#define PI_BAD_SER_DEVICE -79 // bad serial device name
#define PI_BAD_SER_SPEED -80 // bad serial baud rate
#define PI_BAD_PARAM -81 // bad i2c/spi/ser parameter
#define PI_I2C_WRITE_FAILED -82 // i2c write failed
#define PI_I2C_READ_FAILED -83 // i2c read failed
#define PI_BAD_SPI_COUNT -84 // bad SPI count
#define PI_SER_WRITE_FAILED -85 // ser write failed
#define PI_SER_READ_FAILED -86 // ser read failed
#define PI_SER_READ_NO_DATA -87 // ser read no data available
#define PI_UNKNOWN_COMMAND -88 // unknown command
#define PI_SPI_XFER_FAILED -89 // spi xfer/read/write failed
#define PI_BAD_POINTER -90 // bad (NULL) pointer
#define PI_NO_AUX_SPI -91 // need a A+/B+/Pi2 for auxiliary SPI
#define PI_NOT_PWM_GPIO -92 // gpio is not in use for PWM
#define PI_NOT_SERVO_GPIO -93 // gpio is not in use for servo pulses
#define PI_NOT_HCLK_GPIO -94 // gpio has no hardware clock
#define PI_NOT_HPWM_GPIO -95 // gpio has no hardware PWM
#define PI_BAD_HPWM_FREQ -96 // hardware PWM frequency not 1-125M
#define PI_BAD_HPWM_DUTY -97 // hardware PWM dutycycle not 0-1M
#define PI_BAD_HCLK_FREQ -98 // hardware clock frequency not 4689-250M
#define PI_BAD_HCLK_PASS -99 // need password to use hardware clock 1
#define PI_HPWM_ILLEGAL -100 // illegal, PWM in use for main clock
#define PI_BAD_DATABITS -101 // serial data bits not 1-32
#define PI_BAD_STOPBITS -102 // serial (half) stop bits not 2-8
#define PI_MSG_TOOBIG -103 // socket/pipe message too big
#define PI_BAD_MALLOC_MODE -104 // bad memory allocation mode
#define PI_TOO_MANY_SEGS -105 // too many I2C transaction segments
#define PI_BAD_I2C_SEG -106 // an I2C transaction segment failed
#define PI_BAD_SMBUS_CMD -107 // SMBus command not supported by driver
#define PI_NOT_I2C_GPIO -108 // no bit bang I2C in progress on gpio
#define PI_BAD_I2C_WLEN -109 // bad I2C write length
#define PI_BAD_I2C_RLEN -110 // bad I2C read length
#define PI_BAD_I2C_CMD -111 // bad I2C command
#define PI_BAD_I2C_BAUD -112 // bad I2C baud rate, not 50-500k
#define PI_CHAIN_LOOP_CNT -113 // bad chain loop count
#define PI_BAD_CHAIN_LOOP -114 // empty chain loop
#define PI_CHAIN_COUNTER -115 // too many chain counters
#define PI_BAD_CHAIN_CMD -116 // bad chain command
#define PI_BAD_CHAIN_DELAY -117 // bad chain delay micros
#define PI_CHAIN_NESTING -118 // chain counters nested too deeply
#define PI_CHAIN_TOO_BIG -119 // chain is too long
#define PI_DEPRECATED -120 // deprecated function removed
#define PI_BAD_SER_INVERT -121 // bit bang serial invert not 0 or 1
#define PI_PIGIF_ERR_0 -2000
#define PI_PIGIF_ERR_99 -2099
#define PI_CUSTOM_ERR_0 -3000
#define PI_CUSTOM_ERR_999 -3999
/*DEF_E*/
/*DEF_S Defaults*/
#define PI_DEFAULT_BUFFER_MILLIS 120
#define PI_DEFAULT_CLK_MICROS 5
#define PI_DEFAULT_CLK_PERIPHERAL PI_CLOCK_PCM
#define PI_DEFAULT_IF_FLAGS 0
#define PI_DEFAULT_DMA_CHANNEL 14
#define PI_DEFAULT_DMA_PRIMARY_CHANNEL 14
#define PI_DEFAULT_DMA_SECONDARY_CHANNEL 5
#define PI_DEFAULT_SOCKET_PORT 8888
#define PI_DEFAULT_SOCKET_PORT_STR "8888"
#define PI_DEFAULT_SOCKET_ADDR_STR "127.0.0.1"
#define PI_DEFAULT_UPDATE_MASK_R0 0xFFFFFFFF
#define PI_DEFAULT_UPDATE_MASK_R1 0x03E7CF93
#define PI_DEFAULT_UPDATE_MASK_R2 0xFBC7CF9C
#define PI_DEFAULT_UPDATE_MASK_R3 0x0080480FFFFFFCLL
#define PI_DEFAULT_UPDATE_MASK_COMPUTE 0x00FFFFFFFFFFFFLL
#define PI_DEFAULT_MEM_ALLOC_MODE PI_MEM_ALLOC_AUTO
/*DEF_E*/
#endif