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pigpio/pigpio.py

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"""
pigpio is a Python module for the Raspberry Pi which allows control
of the general purpose input outputs (gpios).
There are 54 gpios in total, arranged in two banks. Bank 1 contains
gpios 0-31. Bank 2 contains gpios 32-54.
Most of the gpios are dedicated to system use.
A user should only manipulate gpios in bank 1.
For a Rev.1 board only use gpios 0, 1, 4, 7, 8, 9, 10, 11, 14, 15, 17,
18, 21, 22, 23, 24, 25.
For a Rev.2 board only use gpios 2, 3, 4, 7, 8, 9, 10, 11, 14, 15, 17,
18, 22, 23, 24, 25, 27, 28, 29, 30, 31.
It is safe to read all the gpios. If you try to write a system gpio or
change its mode you can crash the Pi or corrupt the data on the SD card.
Features
The pigpio module's main features are:
- provision of PWM on any number of gpios 0-31 simultaneously.
- provision of servo pulses on any number of gpios 0-31 simultaneously.
- callbacks when any of gpios 0-31 change state.
- reading/writing gpios and setting their modes (typically input
or output).
- reading/writing all of the gpios in a bank (0-31, 32-53) as a single
operation.
Notes
ALL gpios are identified by their Broadcom number.
This module uses the services of the C pigpio library. That library
must be running on the Pi whose gpios are to be manipulated.
The normal way to start the library is as a daemon (during system
start).
sudo pigpiod
Your Python program should wrap the use of the module up in calls
to pigpio.start() and pigpio.stop().
Settings
A number of settings are determined when the pigpiod daemon is started.
- the sample rate (1, 2, 4, 5, 8, or 10us, default 5us).
- the set of gpios which may be updated (generally written to). The
default set is those listed above for the Rev.1 or Rev.2 boards.
- the available PWM frequencies (see set_PWM_frequency()).
Exceptions
By default a fatal exception is raised if you pass an invalid
argument to a pigpio function.
If you wish to handle the returned status yourself you should set
pigpio.exceptions = False.
"""
import socket
import struct
import time
import threading
import os
import atexit
VERSION = "1.0"
# gpio levels
OFF = 0
LOW = 0
CLEAR = 0
ON = 1
HIGH = 1
SET = 1
TIMEOUT = 2
# gpio edges
EITHER_EDGE = 0
RISING_EDGE = 1
FALLING_EDGE = 2
# gpio modes
INPUT = 0
OUTPUT = 1
ALT0 = 4
ALT1 = 5
ALT2 = 6
ALT3 = 7
ALT4 = 3
ALT5 = 2
# gpio Pull Up Down
PUD_OFF = 0
PUD_DOWN = 1
PUD_UP = 2
# pigpio command numbers
_PI_CMD_MODES= 0
_PI_CMD_MODEG= 1
_PI_CMD_PUD= 2
_PI_CMD_READ= 3
_PI_CMD_WRITE= 4
_PI_CMD_PWM= 5
_PI_CMD_PRS= 6
_PI_CMD_PFS= 7
_PI_CMD_SERVO= 8
_PI_CMD_WDOG= 9
_PI_CMD_BR1= 10
_PI_CMD_BR2= 11
_PI_CMD_BC1= 12
_PI_CMD_BC2= 13
_PI_CMD_BS1= 14
_PI_CMD_BS2= 15
_PI_CMD_TICK= 16
_PI_CMD_HWVER=17
_PI_CMD_NO= 18
_PI_CMD_NB= 19
_PI_CMD_NP= 20
_PI_CMD_NC= 21
_PI_CMD_PRG= 22
_PI_CMD_PFG= 23
_PI_CMD_PRRG= 24
_PI_CMD_NOIB= 99
# pigpio error numbers
_PI_INIT_FAILED =-1
PI_BAD_USER_GPIO =-2
PI_BAD_GPIO =-3
PI_BAD_MODE =-4
PI_BAD_LEVEL =-5
PI_BAD_PUD =-6
PI_BAD_PULSEWIDTH =-7
PI_BAD_DUTYCYCLE =-8
_PI_BAD_TIMER =-9
_PI_BAD_MS =-10
_PI_BAD_TIMETYPE =-11
_PI_BAD_SECONDS =-12
_PI_BAD_MICROS =-13
_PI_TIMER_FAILED =-14
PI_BAD_WDOG_TIMEOUT =-15
_PI_NO_ALERT_FUNC =-16
_PI_BAD_CLK_PERIPH =-17
_PI_BAD_CLK_SOURCE =-18
_PI_BAD_CLK_MICROS =-19
_PI_BAD_BUF_MILLIS =-20
PI_BAD_DUTYRANGE =-21
_PI_BAD_SIGNUM =-22
_PI_BAD_PATHNAME =-23
PI_NO_HANDLE =-24
PI_BAD_HANDLE =-25
_PI_BAD_IF_FLAGS =-26
_PI_BAD_CHANNEL =-27
_PI_BAD_PRIM_CHANNEL=-27
_PI_BAD_SOCKET_PORT =-28
_PI_BAD_FIFO_COMMAND=-29
_PI_BAD_SECO_CHANNEL=-30
_PI_NOT_INITIALISED =-31
_PI_INITIALISED =-32
_PI_BAD_WAVE_MODE =-33
_PI_BAD_CFG_INTERNAL=-34
_PI_BAD_WAVE_BAUD =-35
_PI_TOO_MANY_PULSES =-36
_PI_TOO_MANY_CHARS =-37
_PI_NOT_SERIAL_GPIO =-38
_PI_BAD_SERIAL_STRUC=-39
_PI_BAD_SERIAL_BUF =-40
PI_NOT_PERMITTED =-41
PI_SOME_PERMITTED =-42
# pigpio error text
_errors=[
[_PI_INIT_FAILED , "pigpio initialisation failed"],
[PI_BAD_USER_GPIO , "gpio not 0-31"],
[PI_BAD_GPIO , "gpio not 0-53"],
[PI_BAD_MODE , "mode not 0-7"],
[PI_BAD_LEVEL , "level not 0-1"],
[PI_BAD_PUD , "pud not 0-2"],
[PI_BAD_PULSEWIDTH , "pulsewidth not 0 or 500-2500"],
[PI_BAD_DUTYCYCLE , "dutycycle not 0-255"],
[_PI_BAD_TIMER , "timer not 0-9"],
[_PI_BAD_MS , "ms not 10-60000"],
[_PI_BAD_TIMETYPE , "timetype not 0-1"],
[_PI_BAD_SECONDS , "seconds < 0"],
[_PI_BAD_MICROS , "micros not 0-999999"],
[_PI_TIMER_FAILED , "gpioSetTimerFunc failed"],
[PI_BAD_WDOG_TIMEOUT , "timeout not 0-60000"],
[_PI_NO_ALERT_FUNC , "DEPRECATED"],
[_PI_BAD_CLK_PERIPH , "clock peripheral not 0-1"],
[_PI_BAD_CLK_SOURCE , "clock source not 0-1"],
[_PI_BAD_CLK_MICROS , "clock micros not 1, 2, 4, 5, 8, or 10"],
[_PI_BAD_BUF_MILLIS , "buf millis not 100-10000"],
[PI_BAD_DUTYRANGE , "dutycycle range not 25-40000"],
[_PI_BAD_SIGNUM , "signum not 0-63"],
[_PI_BAD_PATHNAME , "can't open pathname"],
[PI_NO_HANDLE , "no handle available"],
[PI_BAD_HANDLE , "unknown notify handle"],
[_PI_BAD_IF_FLAGS , "ifFlags > 3"],
[_PI_BAD_CHANNEL , "DMA channel not 0-14"],
[_PI_BAD_SOCKET_PORT , "socket port not 1024-30000"],
[_PI_BAD_FIFO_COMMAND , "unknown fifo command"],
[_PI_BAD_SECO_CHANNEL , "DMA secondary channel not 0-6"],
[_PI_NOT_INITIALISED , "function called before gpioInitialise"],
[_PI_INITIALISED , "function called after gpioInitialise"],
[_PI_BAD_WAVE_MODE , "waveform mode not 0-1"],
[_PI_BAD_CFG_INTERNAL , "bad parameter in gpioCfgInternals call"],
[_PI_BAD_WAVE_BAUD , "baud rate not 100-250000"],
[_PI_TOO_MANY_PULSES , "waveform has too many pulses"],
[_PI_TOO_MANY_CHARS , "waveform has too many chars"],
[_PI_NOT_SERIAL_GPIO , "no serial read in progress on gpio"],
[PI_NOT_PERMITTED , "no permission to update gpio"],
[PI_SOME_PERMITTED , "no permission to update one or more gpios"]
]
_control = None
_notify = None
_host = ''
_port = 8888
exceptions = True
class _pigpioError(Exception):
"""pigpio module exception"""
def __init__(self, value):
self.value = value
def __str__(self):
return repr(self.value)
def error(pigpio_error):
"""Converts a pigpio error number to a text description.
pigpio_error: an error number (<0) returned by pigpio.
Example
...
print(pigpio.error(-5))
level not 0-1
...
"""
for e in _errors:
if e[0] == pigpio_error:
return e[1]
return "unknown error"
def tickDiff(tStart, tEnd):
"""Calculate the time difference between two ticks.
tStart: the earlier tick.
tEnd: the later tick.
The function handles wrap around as the tick overflows 32 bits.
The returned value is in microseconds.
Example
...
print(pigpio.tickDiff(4294967272, 12))
36
...
"""
tDiff = tEnd - tStart
if tDiff < 0:
tDiff += (1 << 32)
return tDiff
def _u2i(number):
"""Converts a number from unsigned to signed.
number: a 32 bit unsigned number
"""
mask = (2 ** 32) - 1
if number & (1 << 31):
v = number | ~mask
else:
v = number & mask
if v >= 0:
return v;
else:
if exceptions:
raise _pigpioError(error(v))
else:
return v
def _pigpio_command(sock, cmd, p1, p2):
"""Executes a pigpio socket command.
sock: command socket.
cmd: the command to be executed.
p1: command paramter 1 (if applicable).
p2: command paramter 2 (if applicable).
"""
if sock is not None:
sock.send(struct.pack('IIII', cmd, p1, p2, 0))
x, y, z, res = struct.unpack('IIII', sock.recv(16))
return res
else:
raise _pigpioError("*** Module not started, call pigpio.start() ***")
class _callback:
"""An ADT class to hold callback information."""
def __init__(self, gpio, edge, func):
"""Initialises a callback ADT.
gpio: Broadcom gpio number.
edge: EITHER_EDGE, RISING_EDGE, or FALLING_EDGE.
func: a user function taking three arguments (gpio, level, tick).
"""
self.gpio = gpio
self.edge = edge
self.func = func
self.bit = 1<<gpio
class _callback_thread(threading.Thread):
"""A class to encapsulate pigpio notification callbacks."""
def __init__(self):
"""Initialises notifications."""
threading.Thread.__init__(self)
self.daemon = True
self.monitor = 0
self.callbacks = []
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.connect((_host,_port))
self.handle = _pigpio_command(self.sock, _PI_CMD_NOIB, 0, 0)
self.start()
def stop(self):
"""Stops notifications."""
if self.go:
self.go = False
self.sock.send(struct.pack('IIII', _PI_CMD_NC, self.handle, 0, 0))
def append(self, callb):
"""Adds a callback to the notification thread.
callb:
"""
self.callbacks.append(callb)
self.monitor = self.monitor | callb.bit
notify_begin(self.handle, self.monitor)
def remove(self, callb):
"""Removes a callback from the notification thread.
callb:
"""
if callb in self.callbacks:
self.callbacks.remove(callb)
newMonitor = 0
for c in self.callbacks:
newMonitor |= c.bit
if newMonitor != self.monitor:
self.monitor = newMonitor
notify_begin(self.handle, self.monitor)
def run(self):
"""Execute the notification thread."""
self.go = True
lastLevel = 0
while self.go:
seq_no, flags, tick, level = (
struct.unpack('HHII', self.sock.recv(12, socket.MSG_WAITALL)))
if self.go:
if flags == 0:
changed = level ^ lastLevel
lastLevel = level
for cb in self.callbacks:
if cb.bit & changed:
newLevel = 0
if cb.bit & level:
newLevel = 1
if (cb.edge == EITHER_EDGE or
cb.edge == RISING_EDGE and newLevel == 1 or
cb.edge == FALLING_EDGE and newLevel == 0):
cb.func(cb.gpio, newLevel, tick)
else:
gpio = flags & 31
for cb in self.callbacks:
if cb.gpio == gpio:
cb.func(cb.gpio, TIMEOUT, tick)
self.sock.close()
class _wait_for_edge:
"""A class to encapsulate waiting for gpio edges."""
def __init__(self, gpio, edge, timeout):
"""Initialise a wait_for_edge.
gpio:
edge:
timeout:
"""
self.callb = _callback(gpio, edge, self.func)
self.trigger = False
_notify.append(self.callb)
self.start = time.time()
while (self.trigger == False) and ((time.time()-self.start) < timeout):
time.sleep(0.1)
_notify.remove(self.callb)
def func(self, gpio, level, tick):
"""Set wait_for_edge triggered.
gpio:
level:
tick:
"""
self.trigger = True
def set_mode(gpio, mode):
"""Set the gpio mode.
gpio: 0-53.
mode: INPUT, OUTPUT, ALT0, ALT1, ALT2, ALT3, ALT4, ALT5.
Returns 0 if OK, otherwise PI_BAD_GPIO, PI_BAD_MODE,
or PI_NOT_PERMITTED.
Notes
Arduino style: pinMode.
Example
...
pigpio.set_mode(4, pigpio.INPUT) # gpio 4 as input
pigpio.set_mode(7, pigpio.OUTPUT) # gpio 7 as output
pigpio.set_mode(10, pigpio.ALT2) # gpio 10 as ALT2
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_MODES, gpio, mode))
return r
def get_mode(gpio):
"""Get the gpio mode.
Returns the gpio mode if OK, otherwise PI_BAD_GPIO.
gpio: 0-53.
Example
...
print(pigpio.get_mode(4))
0
print(pigpio.get_mode(7))
1
print(pigpio.get_mode(10))
6
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_MODEG, gpio, 0))
return r
def set_pull_up_down(gpio, pud):
"""Set or clear the gpio pull-up/down resistor.
Returns 0 if OK, otherwise PI_BAD_GPIO, PI_BAD_PUD,
or PI_NOT_PERMITTED.
gpio: 0-53.
pud: PUD_UP, PUD_DOWN, PUD_OFF.
Example
...
pigpio.set_mode(23, pigpio.INPUT)
pigpio.set_mode(24, pigpio.INPUT)
pigpio.set_pull_up_down(23, pigpio.PUD_UP)
pigpio.set_pull_up_down(24, pigpio.PUD_DOWN)
print(pigpio.read(23))
1
print(pigpio.read(24))
0
pigpio.set_pull_up_down(23, pigpio.PUD_DOWN)
pigpio.set_pull_up_down(24, pigpio.PUD_UP)
print(pigpio.read(23))
0
print(pigpio.read(24))
1
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PUD, gpio, pud))
return r
def read(gpio):
"""Read the gpio level.
Returns the gpio level if OK, otherwise PI_BAD_GPIO.
gpio:0-53.
Notes
Arduino style: digitalRead.
Example
...
pigpio.set_mode(25, pigpio.INPUT)
pigpio.set_pull_up_down(25, pigpio.PUD_DOWN)
print(pigpio.read(25))
0
pigpio.set_pull_up_down(25, pigpio.PUD_UP)
print(pigpio.read(25))
1
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_READ, gpio, 0))
return r
def write(gpio, level):
"""Write the gpio level.
Returns 0 if OK, otherwise PI_BAD_GPIO, PI_BAD_LEVEL,
or PI_NOT_PERMITTED.
gpio: 0-53.
level: 0, 1.
Notes
If PWM or servo pulses are active on the gpio they are switched off.
Arduino style: digitalWrite
Example
...
pigpio.set_mode(11, pigpio.OUTPUT)
pigpio.write(11,0)
print(pigpio.read(11))
0
pigpio.write(11,1)
print(pigpio.read(11))
1
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_WRITE, gpio, level))
return r
def set_PWM_dutycycle(user_gpio, dutycycle):
"""Start (non-zero dutycycle) or stop (0) PWM pulses on the gpio.
Returns 0 if OK, otherwise PI_BAD_USER_GPIO, PI_BAD_DUTYCYCLE,
or PI_NOT_PERMITTED.
user_gpio: 0-31.
dutycycle: 0-range (range defaults to 255).
Notes
Arduino style: analogWrite
This and the servo functionality use the DMA and PWM or PCM
peripherals to control and schedule the pulse lengths and
duty cycles.
The set_PWM_range() function can change the default range of 255.
Example
...
set_PWM_dutycycle(4, 0) # PWM off
set_PWM_dutycycle(4, 64) # PWM 1/4 on
set_PWM_dutycycle(4, 128) # PWM 1/2 on
set_PWM_dutycycle(4, 192) # PWM 3/4 on
set_PWM_dutycycle(4, 255) # PWM full on
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PWM, user_gpio, dutycycle))
return r
def set_PWM_range(user_gpio, range_):
"""Set the range of PWM values to be used on the gpio.
Returns 0 if OK, otherwise PI_BAD_USER_GPIO, PI_BAD_DUTYRANGE,
or PI_NOT_PERMITTED.
user_gpio: 0-31.
range_: 25-40000.
Notes
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 of the 18 available gpio frequencies is
25(#1), 50(#2), 100(#3), 125(#4), 200(#5), 250(#6), 400(#7),
500(#8), 625(#9), 800(#10), 1000(#11), 1250(#12), 2000(#13),
2500(#14), 4000(#15), 5000(#16), 10000(#17), 20000(#18)
The real value set by set_PWM_range is
(dutycycle * real range) / range.
Example
...
pigpio.set_PWM_range(9, 100) # now 25 1/4, 50 1/2, 75 3/4 on
pigpio.set_PWM_range(9, 500) # now 125 1/4, 250 1/2, 375 3/4 on
pigpio.set_PWM_range(9, 3000) # now 750 1/4, 1500 1/2, 2250 3/4 on
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PRS, user_gpio, range_))
return r
def get_PWM_range(user_gpio):
"""Get the range of PWM values being used on the gpio.
Returns the dutycycle range used for the gpio if OK,
otherwise PI_BAD_USER_GPIO.
user_gpio: 0-31.
Example
...
print(pigpio.get_PWM_range(9))
255
pigpio.set_PWM_range(9, 100)
print(pigpio.get_PWM_range(9))
100
pigpio.set_PWM_range(9, 500)
print(pigpio.get_PWM_range(9))
500
pigpio.set_PWM_range(9, 3000)
print(pigpio.get_PWM_range(9))
3000
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PRG, user_gpio, 0))
return r
def get_PWM_real_range(user_gpio):
"""Get the real underlying range of PWM values being used on the gpio.
Returns the real range used for the gpio if OK,
otherwise PI_BAD_USER_GPIO.
user_gpio: 0-31.
Example
...
pigpio.set_PWM_frequency(4,0)
print(pigpio.get_PWM_real_range(4))
20000
pigpio.set_PWM_frequency(4,800)
print(pigpio.get_PWM_real_range(4))
250
pigpio.set_PWM_frequency(4,100000)
print(pigpio.get_PWM_real_range(4))
25
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PRRG, user_gpio, 0))
return r
def set_PWM_frequency(user_gpio, frequency):
"""Set the frequency (in Hz) of the PWM to be used on the gpio.
Returns the numerically closest frequency if OK, otherwise
PI_BAD_USER_GPIO or PI_NOT_PERMITTED.
user_gpio: 0-31.
frequency: 0- (Hz).
The selectable frequencies depend upon the sample rate which
may be 1, 2, 4, 5, 8, or 10 microseconds (default 5). The
sample rate is set when the C pigpio library is started.
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.
1us 40000, 20000, 10000, 8000, 5000, 4000, 2500, 2000, 1600,
1250, 1000, 800, 500, 400, 250, 200, 100, 50
2us 20000, 10000, 5000, 4000, 2500, 2000, 1250, 1000, 800,
625, 500, 400, 250, 200, 125, 100, 50, 25
4us 10000, 5000, 2500, 2000, 1250, 1000, 625, 500, 400,
313, 250, 200, 125, 100, 63, 50, 25, 13
5us 8000, 4000, 2000, 1600, 1000, 800, 500, 400, 320,
250, 200, 160, 100, 80, 50, 40, 20, 10
8us 5000, 2500, 1250, 1000, 625, 500, 313, 250, 200,
156, 125, 100, 63, 50, 31, 25, 13, 6
10us 4000, 2000, 1000, 800, 500, 400, 250, 200, 160,
125, 100, 80, 50, 40, 25, 20, 10, 5
Example
...
pigpio.set_PWM_frequency(4,0)
print(pigpio.get_PWM_frequency(4))
10
pigpio.set_PWM_frequency(4,800)
print(pigpio.get_PWM_frequency(4))
800
pigpio.set_PWM_frequency(4,100000)
print(pigpio.get_PWM_frequency(4))
8000
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PFS, user_gpio, frequency))
return r
def get_PWM_frequency(user_gpio):
"""Get the frequency of PWM being used on the gpio.
Returns the frequency (in hertz) used for the gpio if OK,
otherwise PI_BAD_USER_GPIO.
user_gpio: 0-31.
Example
...
pigpio.set_PWM_frequency(4,0)
print(pigpio.get_PWM_frequency(4))
10
pigpio.set_PWM_frequency(4,800)
print(pigpio.get_PWM_frequency(4))
800
pigpio.set_PWM_frequency(4,100000)
print(pigpio.get_PWM_frequency(4))
8000
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_PFG, user_gpio, 0))
return r
def set_servo_pulsewidth(user_gpio, pulsewidth):
"""Start (500-2500) or stop (0) servo pulses on the gpio.
Returns 0 if OK, otherwise PI_BAD_USER_GPIO, PI_BAD_PULSEWIDTH or
PI_NOT_PERMITTED.
user_gpio: 0-31.
pulsewidth: 0 (off), 500 (most anti-clockwise) - 2500 (most clockwise).
The selected pulsewidth will continue to be transmitted until
changed by a subsequent call to set_servo_pulsewidth().
The pulsewidths 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.
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.
Update Rate (Hz) 50 100 200 400 500
1E6/Hz 20000 10000 5000 2500 2000
Firstly set the desired PWM frequency using set_PWM_frequency().
Then set the PWM range using set_PWM_range() to 1E6/Hz.
Doing this allows you to use units of microseconds when setting
the servo pulse width.
E.g. If you want to update a servo connected to gpio 25 at 400Hz
set_PWM_frequency(25, 400)
set_PWM_range(25, 2500)
Thereafter use the set_PWM_dutycycle() function to move the servo,
e.g. set_PWM_dutycycle(25, 1500) will set a 1500 us pulse.
Example 1: standard 50 Hz hobby servo updates
#!/usr/bin/python
import pigpio
import time
moves = [[1000, 5],[1200,3],[1500,2],[2000,5],[1000,0]]
pigpio.start()
for m in moves:
pigpio.set_servo_pulsewidth(24, m[0]);
time.sleep(m[1])
message = str(m[1]) + " seconds @ " + str(m[0]) + " us"
print(message)
pigpio.stop()
will print lines
5 seconds @ 1000 us
3 seconds @ 1200 us
2 seconds @ 1500 us
5 seconds @ 2000 us
0 seconds @ 1000 us
Example 2: 400 Hz ESC type servo updates
#!/usr/bin/python
import pigpio
import time
moves = [[1000, 5],[1200,3],[1500,2],[2000,5],[1000,0]]
pigpio.start()
pigpio.set_PWM_frequency(25, 400)
pigpio.set_PWM_range(25, 2500)
for m in moves:
pigpio.set_PWM_dutycycle(25, m[0]);
time.sleep(m[1])
message = str(m[1]) + " seconds @ " + str(m[0]) + " us"
print(message)
pigpio.stop()
will print lines
5 seconds @ 1000 us
3 seconds @ 1200 us
2 seconds @ 1500 us
5 seconds @ 2000 us
0 seconds @ 1000 us
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_SERVO, user_gpio, pulsewidth))
return r
def notify_open():
"""Get 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.
Pipes are only accessible from the local machine so this function
serves no purpose if you are using Python from a remote machine.
The in-built (socket) notifications provided by callback()
should be used instead.
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.
Example
...
h = pigpio.notify_open()
if h >= 0:
pigpio.notify_begin(h, 1234)
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_NO, 0, 0))
return r
def notify_begin(handle, bits):
"""Start notifications on a previously opened handle.
Returns 0 if OK, otherwise PI_BAD_HANDLE.
handle: 0-31 (as returned by notify_open())
bits: a mask indicating the gpios to be notified.
The notification sends state changes for each gpio whose
corresponding bit in bits is set.
Example
...
h = pigpio.notify_open()
if h >= 0:
pigpio.notify_begin(h, 1234)
...
This will start notifications for gpios 1, 4, 6, 7, 10
(1234 = 0x04D2 = 0b0000010011010010).
Notes
Each notification occupies 12 bytes in the fifo as follows:
H (16 bit) seqno
H (16 bit) flags
I (32 bit) tick
I (32 bit) level
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_NB, handle, bits))
return r
def notify_pause(handle):
"""Pause notifications on a previously opened handle.
Returns 0 if OK, otherwise PI_BAD_HANDLE.
handle: 0-31 (as returned by notify_open())
Notifications for the handle are suspended until
notify_begin() is called again.
Example
...
h = pigpio.notify_open()
if h >= 0:
pigpio.notify_begin(h, 1234)
...
pigpio.notify_pause(h)
...
pigpio.notify_begin(h, 1234)
...
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_NB, handle, 0))
return r
def notify_close(handle):
"""Stop notifications on a previously opened handle and
release the handle for reuse.
Returns 0 if OK, otherwise PI_BAD_HANDLE.
handle: 0-31 (as returned by notify_open())
Example
...
h = pigpio.notify_open()
if h >= 0:
pigpio.notify_begin(h, 1234)
...
pigpio.notify_close(h)
...
...
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_NC, handle, 0))
return r
def set_watchdog(user_gpio, timeout):
"""Sets a watchdog for a gpio.
Returns 0 if OK, otherwise PI_BAD_USER_GPIO
or PI_BAD_WDOG_TIMEOUT.
user_gpio: 0-31.
timeout: 0-60000.
The watchdog is nominally in milliseconds.
Only 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 any notification for the gpio has a report written
to the fifo with the flags set to indicate a watchdog timeout.
The callback() class interprets the flags and will
call registered callbacks for the gpio with level TIMEOUT.
Example
#!/usr/bin/python
import pigpio
import time
def cbf(g, L, t):
message = "gpio=" + str(g) + " level=" + str(L) + " at " + str(t)
print(message)
pigpio.start()
cb = pigpio.callback(22, pigpio.EITHER_EDGE, cbf)
print("callback started, 5 second delay")
time.sleep(5)
pigpio.set_watchdog(22, 1000) # 1000ms watchdog
print("watchdog started, 5 second delay")
time.sleep(5)
pigpio.set_watchdog(22, 0) # cancel watchdog
print("watchdog cancelled, 5 second delay")
time.sleep(5)
cb.cancel()
pigpio.stop()
will print lines such as
callback started, 5 second delay
watchdog started, 5 second delay
gpio=22 level=2 at 3547411617
gpio=22 level=2 at 3548411254
gpio=22 level=2 at 3549411927
gpio=22 level=2 at 3550412060
gpio=22 level=2 at 3551411622
watchdog cancelled, 5 second delay
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_WDOG, user_gpio, timeout))
return r
def read_bank_1():
"""Read the levels of the bank 1 gpios (gpios 0-31).
The returned 32 bit integer has a bit set if the corresponding
gpio is logic 1. Gpio n has bit value (1<<n).
Example
...
print(bin(pigpio.read_bank_1()))
0b10010100000011100100001001111
...
"""
return _pigpio_command(_control, _PI_CMD_BR1, 0, 0)
def read_bank_2():
"""Read the levels of the bank 2 gpios (gpios 32-53).
The returned 32 bit integer has a bit set if the corresponding
gpio is logic 1. Gpio n has bit value (1<<(n-32)).
Example
...
print(bin(pigpio.read_bank_2()))
0b1111110000000000000000
...
"""
return _pigpio_command(_control, _PI_CMD_BR2, 0, 0)
def clear_bank_1(levels):
"""Clears gpios 0-31 if the corresponding bit in levels is set.
Returns 0 if OK, otherwise PI_SOME_PERMITTED.
A status of PI_SOME_PERMITTED indicates that the user is not
allowed to write to one or more of the gpios.
levels: a bit mask with 1 set if the corresponding gpio is
to be cleared.
Example
#!/usr/bin/python
import pigpio
pigpio.start()
pigpio.set_mode(4, pigpio.OUTPUT)
pigpio.set_mode(7, pigpio.OUTPUT)
pigpio.set_mode(8, pigpio.OUTPUT)
pigpio.set_mode(9, pigpio.OUTPUT)
pigpio.set_mode(10, pigpio.OUTPUT)
pigpio.set_mode(11, pigpio.OUTPUT)
pigpio.set_bank_1(int("111110010000",2))
# 0x1000 is added so that all numbers are aligned
b1 = (pigpio.read_bank_1() & 0xFFF) + 0x1000
print(bin(b1))
pigpio.clear_bank_1(int("111110010000",2))
b2 = (pigpio.read_bank_1() & 0xFFF) + 0x1000
print(bin(b2))
print(bin((b1^b2) + 0x1000))
pigpio.stop()
displays
0b1111111011111
0b1000001001111
0b1111110010000
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_BC1, levels, 0))
return r
def clear_bank_2(levels):
"""Clears gpios 32-53 if the corresponding bit (0-21) in levels is set.
Returns 0 if OK, otherwise PI_SOME_PERMITTED.
A status of PI_SOME_PERMITTED indicates that the user is not
allowed to write to one or more of the gpios.
levels: a bit mask with 1 set if the corresponding gpio is
to be cleared.
See clear_bank_1() for an example.
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_BC2, levels, 0))
return r
def set_bank_1(levels):
"""Sets gpios 0-31 if the corresponding bit in levels is set.
Returns 0 if OK, otherwise PI_SOME_PERMITTED.
A status of PI_SOME_PERMITTED indicates that the user is not
allowed to write to one or more of the gpios.
levels: a bit mask with 1 set if the corresponding gpio is
to be set.
Example
#!/usr/bin/python
import pigpio
pigpio.start()
pigpio.set_mode(4, pigpio.OUTPUT)
pigpio.set_mode(7, pigpio.OUTPUT)
pigpio.set_mode(8, pigpio.OUTPUT)
pigpio.set_mode(9, pigpio.OUTPUT)
pigpio.set_mode(10, pigpio.OUTPUT)
pigpio.set_mode(11, pigpio.OUTPUT)
pigpio.clear_bank_1(int("111110010000",2))
# 0x1000 is added so that all numbers are aligned
b1 = (pigpio.read_bank_1() & 0xFFF) + 0x1000
print(bin(b1))
pigpio.set_bank_1(int("111110010000",2))
b2 = (pigpio.read_bank_1() & 0xFFF) + 0x1000
print(bin(b2))
print(bin((b1^b2) + 0x1000))
pigpio.stop()
displays
0b1000001001111
0b1111111011111
0b1111110010000
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_BS1, levels, 0))
return r
def set_bank_2(levels):
"""Sets gpios 32-53 if the corresponding bit (0-21) in levels is set.
Returns 0 if OK, otherwise PI_SOME_PERMITTED.
A status of PI_SOME_PERMITTED indicates that the user is not
allowed to write to one or more of the gpios.
levels: a bit mask with 1 set if the corresponding gpio is
to be set.
See set_bank_1() for an example.
"""
r=_u2i(_pigpio_command(_control, _PI_CMD_BS2, levels, 0))
return r
def get_current_tick():
"""Gets 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.
Example
#!/usr/bin/python
import pigpio
import time
pigpio.start()
t1 = pigpio.get_current_tick()
time.sleep(5)
t2 = pigpio.get_current_tick()
message = "5 seconds is " + str(pigpio.tickDiff(t1, t2)) + " ticks"
print(message)
pigpio.stop()
displays
5 seconds is 5003398 ticks
"""
return _pigpio_command(_control, _PI_CMD_TICK, 0, 0)
def get_hardware_revision():
"""Get the Pi's hardware revision number.
It is unfortunate that Pi boards have been named Revision.1 and
Revision.2. That use of the word revision is distinct from the
Pi's hardware revision number.'
The hardware revision is the last 4 characters on the Revision line
of /proc/cpuinfo.
The revision number can be used to determine the assignment of gpios
to pins.
There are at least two types of board.
Type 1 has gpio 0 on P1-3, gpio 1 on P1-5, and gpio 21 on P1-13.
Type 2 has gpio 2 on P1-3, gpio 3 on P1-5, gpio 27 on P1-13, and
gpios 28-31 on P5.
Type 1 boards have hardware revision numbers of 2 and 3.
Type 2 boards have hardware revision numbers of 4, 5, 6, and 15.
If the hardware revision can not be found or is not a valid
hexadecimal number the function returns 0.
Example 1:
...
print(pigpio.get_hardware_revision())
2
...
Example 2:
for "Revision : 0002" the function returns 2.
for "Revision : 000f" the function returns 15.
for "Revision : 000g" the function returns 0.
"""
return _pigpio_command(_control, _PI_CMD_HWVER, 0, 0)
class callback:
"""A class to provide gpio level change callbacks."""
def __init__(self, user_gpio, edge=RISING_EDGE, func=None):
"""Initialise a callback and adds it to the notification thread.
user_gpio: 0-31.
edge: EITHER_EDGE, RISING_EDGE (default), or FALLING_EDGE.
func: user supplied callback function.
If a user callback is not specified a default tally callback is
provided which simply counts edges.
The user supplied callback receives three parameters, the gpio,
the level, and the tick.
Example 1: user supplied edge and callback
#!/usr/bin/python
import pigpio
import time
def cbf(g, L, t):
message = "gpio=" + str(g) + " level=" + str(L) + " at " + str(t)
print(message)
pigpio.start()
cb = pigpio.callback(22, pigpio.EITHER_EDGE, cbf)
time.sleep(30)
cb.cancel()
pigpio.stop()
will print lines such as
gpio=22 level=1 at 548556842
gpio=22 level=0 at 551316679
gpio=22 level=1 at 553411795
gpio=22 level=0 at 555269219
gpio=22 level=1 at 557689701
Example 2: user supplied edge, default (tally) callback
#!/usr/bin/python
import pigpio
import time
pigpio.start()
pigpio.set_PWM_dutycycle(4, 0)
pigpio.set_PWM_frequency(4, 2000)
cb = pigpio.callback(4, pigpio.EITHER_EDGE)
pigpio.set_PWM_dutycycle(4, 128) # half power
tally_1 = cb.tally()
time.sleep(50)
tally_2 = cb.tally()
message = "counted " + str(tally_2 - tally_1) + " edges"
print(message)
cb.cancel()
pigpio.stop()
will print a line such as
counted 200200 edges
Example 3: default edge and (tally) callback
#!/usr/bin/python
import pigpio
import time
pigpio.start()
pigpio.set_PWM_dutycycle(17, 0)
pigpio.set_PWM_frequency(17, 2000)
cb = pigpio.callback(17)
pigpio.set_PWM_dutycycle(17, 64) # quarter power
tally_1 = cb.tally()
time.sleep(50)
tally_2 = cb.tally()
message = "counted " + str(tally_2 - tally_1) + " rising edges"
print(message)
cb.cancel()
pigpio.stop()
will print a line such as
counted 100101 rising edges
"""
self.count=0
if func is None:
func=self._tally
self.callb = _callback(user_gpio, edge, func)
_notify.append(self.callb)
def cancel(self):
"""Cancels a callback by removing it from the notification thread."""
_notify.remove(self.callb)
def _tally(self, user_gpio, level, tick):
"""Increment the callback called count.
user_gpio:
level:
tick:
"""
self.count += 1
def tally(self):
"""Provides a count of how many times the default tally
callback has triggered.
The count will be zero if the user has supplied their own
callback function.
"""
return self.count
def wait_for_edge(user_gpio, edge=RISING_EDGE, timeout=60.0):
"""Wait for an edge event on a gpio.
The function returns as soon as the edge is detected
or after the number of seconds specified by timeout has
expired.
user_gpio: 0-31.
edge: EITHER_EDGE, RISING_EDGE (default), or FALLING_EDGE.
timeout: 0.0- (default 60.0).
The function returns True if the edge is detected,
otherwise False.
Example 1: default edge and timeout
#!/usr/bin/python
import pigpio
import time
pigpio.start()
if pigpio.wait_for_edge(23):
print("Rising edge detected")
else:
print("wait for edge timed out")
pigpio.stop()
will print
Rising edge detected
or
wait for edge timed out
Example 2: user supplied edge and timeout
#!/usr/bin/python
import pigpio
import time
pigpio.start()
if pigpio.wait_for_edge(23, pigpio.FALLING_EDGE, 5.0):
print("Falling edge detected")
else:
print("wait for falling edge timed out")
pigpio.stop()
will print
Falling edge detected
or
wait for falling edge timed out
"""
a = _wait_for_edge(user_gpio, edge, timeout)
return a.trigger
def start(host = os.getenv("PIGPIO_ADDR", ''),
port = os.getenv("PIGPIO_PORT", 8888)):
"""Start the pigpio module.
host: the host name of the Pi on which the pigpio daemon is running.
The default is localhost unless overwritten by the PIGPIO_ADDR
environment variable.
port: the port number on which the pigpio daemon is listening.
The default is 8888 unless overwritten by the PIGPIO_PORT
environment variable. The pigpiod must have been started
with the same port number.
The function connects to the pigpio daemon and reserves resources
to be used for sending commands and receiving notifications.
EXAMPLES:
...
pigpio.start() # use defaults
pigpio.start('mypi') # specify host, default port
pigpio.start('mypi', 7777) # specify host and port
...
"""
global _control, _notify
global _host, _port
_host = host
_port = int(port)
_control = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
_control.connect((_host, _port))
_notify = _callback_thread()
except socket.error:
if _control is not None:
_control = None
if _host == '':
h = "localhost"
else:
h = _host
errStr = "Can't connect to pigpio on " + str(h) + "(" + str(_port) + ")"
print("********************************************************")
print(errStr)
print("")
print("Did you start the pigpio daemon?")
print("(sudo pigpiod)")
print("")
print("Did you specify the correct Pi host/port in the environment")
print("variables PIGPIO_ADDR/PIGPIO_PORT?")
print("(e.g. export PIGPIO_ADDR=soft, export PIGPIO_PORT=8888)")
print("")
print("Did you specify the correct Pi host/port in the")
print("pigpio.start() function")
print("(e.g. pigpio.start('soft', 8888))")
print("********************************************************")
raise
def stop():
"""Release pigpio resources.
Example
...
pigpio.stop()
...
"""
global _control, _notify
if _notify is not None:
_notify.stop()
_notify = None
if _control is not None:
_control.close()
_control = None
atexit.register(stop)
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