#include "module.h" #include "lauxlib.h" #include "lmem.h" #include "platform.h" #include #include #include #include "user_interface.h" #include "driver/uart.h" #include "osapi.h" #include "cpu_esp8266_irq.h" #include "pixbuf.h" #define MODE_SINGLE 0 #define MODE_DUAL 1 // Init UART1 to be able to stream WS2812 data to GPIO2 pin // If DUAL mode is selected, init UART0 to stream to TXD0 as well // You HAVE to redirect LUA's output somewhere else static int ws2812_init(lua_State* L) { const int mode = luaL_optinteger(L, 1, MODE_SINGLE); luaL_argcheck(L, mode == MODE_SINGLE || mode == MODE_DUAL, 1, "ws2812.SINGLE or ws2812.DUAL expected"); // Configure UART1 // Set baudrate of UART1 to 3200000 WRITE_PERI_REG(UART_CLKDIV(1), UART_CLK_FREQ / 3200000); // Set UART Configuration No parity / 6 DataBits / 1 StopBits / Invert TX WRITE_PERI_REG(UART_CONF0(1), UART_TXD_INV | (1 << UART_STOP_BIT_NUM_S) | (1 << UART_BIT_NUM_S)); if (mode == MODE_DUAL) { // Configure UART0 // Set baudrate of UART0 to 3200000 WRITE_PERI_REG(UART_CLKDIV(0), UART_CLK_FREQ / 3200000); // Set UART Configuration No parity / 6 DataBits / 1 StopBits / Invert TX WRITE_PERI_REG(UART_CONF0(0), UART_TXD_INV | (1 << UART_STOP_BIT_NUM_S) | (1 << UART_BIT_NUM_S)); } // Pull GPIO2 down platform_gpio_mode(4, PLATFORM_GPIO_OUTPUT, PLATFORM_GPIO_FLOAT); platform_gpio_write(4, 0); // Waits 10us to simulate a reset os_delay_us(10); // Redirect UART1 to GPIO2 // Disable GPIO2 GPIO_REG_WRITE(GPIO_ENABLE_W1TC_ADDRESS, BIT2); // Enable Function 2 for GPIO2 (U1TXD) PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_U1TXD_BK); return 0; } static bool ws2812_can_write(int uart) { // If something to send for first buffer and enough room // in FIFO buffer (we wants to write 4 bytes, so less than // 124 in the buffer) return (((READ_PERI_REG(UART_STATUS(uart)) >> UART_TXFIFO_CNT_S) & UART_TXFIFO_CNT) <= 124); } static void ws2812_write_byte(int uart, uint8_t value) { // Data are sent LSB first, with a start bit at 0, an end bit at 1 and all inverted // 0b00110111 => 110111 => [0]111011[1] => 10001000 => 00 // 0b00000111 => 000111 => [0]111000[1] => 10001110 => 01 // 0b00110100 => 110100 => [0]001011[1] => 11101000 => 10 // 0b00000100 => 000100 => [0]001000[1] => 11101110 => 11 // Array declared as static const to avoid runtime generation // But declared in ".data" section to avoid read penalty from FLASH static const __attribute__((section(".data._uartData"))) uint8_t _uartData[4] = { 0b00110111, 0b00000111, 0b00110100, 0b00000100 }; WRITE_PERI_REG(UART_FIFO(uart), _uartData[(value >> 6) & 3]); WRITE_PERI_REG(UART_FIFO(uart), _uartData[(value >> 4) & 3]); WRITE_PERI_REG(UART_FIFO(uart), _uartData[(value >> 2) & 3]); WRITE_PERI_REG(UART_FIFO(uart), _uartData[(value >> 0) & 3]); } // Stream data using UART1 routed to GPIO2 // ws2812.init() should be called first // // NODE_DEBUG should not be activated because it also uses UART1 void ICACHE_RAM_ATTR ws2812_write_data(const uint8_t *pixels, uint32_t length, const uint8_t *pixels2, uint32_t length2) { const uint8_t *end = pixels + length; const uint8_t *end2 = pixels2 + length2; /* Fill the UART fifos with IRQs disabled */ uint32_t irq_state = esp8266_defer_irqs(); while ((pixels < end) && ws2812_can_write(1)) { ws2812_write_byte(1, *pixels++); } while ((pixels2 < end2) && ws2812_can_write(0)) { ws2812_write_byte(0, *pixels2++); } esp8266_restore_irqs(irq_state); do { if (pixels < end && ws2812_can_write(1)) { ws2812_write_byte(1, *pixels++); } // Same for the second buffer if (pixels2 < end2 && ws2812_can_write(0)) { ws2812_write_byte(0, *pixels2++); } } while(pixels < end || pixels2 < end2); // Until there is still something to send } // Lua: ws2812.write("string") // Byte triples in the string are interpreted as G R B values. // // ws2812.init() should be called first // // ws2812.write(string.char(0, 255, 0)) sets the first LED red. // ws2812.write(string.char(0, 0, 255):rep(10)) sets ten LEDs blue. // ws2812.write(string.char(255, 0, 0, 255, 255, 255)) first LED green, second LED white. // // In DUAL mode 'ws2812.init(ws2812.DUAL)', you may pass a second string as parameter // It will be sent through TXD0 in parallel static int ws2812_write(lua_State* L) { size_t length1, length2; const char *buffer1, *buffer2; // First mandatory parameter int type = lua_type(L, 1); if (type == LUA_TNIL) { buffer1 = 0; length1 = 0; } else if(type == LUA_TSTRING) { buffer1 = lua_tolstring(L, 1, &length1); } else if (type == LUA_TUSERDATA) { pixbuf *buffer = pixbuf_from_lua_arg(L, 1); luaL_argcheck(L, pixbuf_channels(buffer) == 3, 1, "Bad pixbuf format"); buffer1 = buffer->values; length1 = pixbuf_size(buffer); } else { luaL_argerror(L, 1, "pixbuf or string expected"); } // Second optionnal parameter type = lua_type(L, 2); if (type == LUA_TNONE || type == LUA_TNIL) { buffer2 = 0; length2 = 0; } else if (type == LUA_TSTRING) { buffer2 = lua_tolstring(L, 2, &length2); } else if (type == LUA_TUSERDATA) { pixbuf *buffer = pixbuf_from_lua_arg(L, 2); luaL_argcheck(L, pixbuf_channels(buffer) == 3, 2, "Bad pixbuf format"); buffer2 = buffer->values; length2 = pixbuf_size(buffer); } else { luaL_argerror(L, 2, "pixbuf or string expected"); } // Send the buffers ws2812_write_data(buffer1, length1, buffer2, length2); return 0; } LROT_BEGIN(ws2812, NULL, 0) LROT_FUNCENTRY( init, ws2812_init ) LROT_FUNCENTRY( newBuffer, pixbuf_new_lua ) // backwards compatibility LROT_FUNCENTRY( write, ws2812_write ) LROT_NUMENTRY( FADE_IN, PIXBUF_FADE_IN ) // BC LROT_NUMENTRY( FADE_OUT, PIXBUF_FADE_OUT ) // BC LROT_NUMENTRY( MODE_SINGLE, MODE_SINGLE ) LROT_NUMENTRY( MODE_DUAL, MODE_DUAL ) LROT_NUMENTRY( SHIFT_LOGICAL, PIXBUF_SHIFT_LOGICAL ) // BC LROT_NUMENTRY( SHIFT_CIRCULAR, PIXBUF_SHIFT_CIRCULAR ) // BC LROT_END(ws2812, NULL, 0) static int luaopen_ws2812(lua_State *L) { // TODO: Make sure that the GPIO system is initialized return 0; } NODEMCU_MODULE(WS2812, "ws2812", ws2812, luaopen_ws2812);