#include "module.h" #include "lauxlib.h" #include "platform.h" #include "c_stdlib.h" #include "c_string.h" /** * Code is based on https://github.com/CHERTS/esp8266-devkit/blob/master/Espressif/examples/EspLightNode/user/ws2801.c * and provides a similar api as the ws2812 module. * The current implementation allows the caller to use * any combination of GPIO0, GPIO2, GPIO4, GPIO5 as clock and data. */ #define PIN_CLK_DEFAULT 0 #define PIN_DATA_DEFAULT 2 static uint32_t ws2801_bit_clk; static uint32_t ws2801_bit_data; static void ws2801_byte(uint8_t n) { uint8_t bitmask; for (bitmask = 0x80; bitmask !=0 ; bitmask >>= 1) { if (n & bitmask) { GPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, ws2801_bit_data); } else { GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, ws2801_bit_data); } GPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, ws2801_bit_clk); GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, ws2801_bit_clk); } } static void ws2801_color(uint8_t r, uint8_t g, uint8_t b) { ws2801_byte(r); ws2801_byte(g); ws2801_byte(b); } static void ws2801_strip(uint8_t const * data, uint16_t len) { while (len--) { ws2801_byte(*(data++)); } GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, ws2801_bit_data); } static void enable_pin_mux(int pin) { // The API only supports setting PERIPHS_IO_MUX on GPIO 0, 2, 4, 5 switch (pin) { case 0: PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO0_U, FUNC_GPIO0); break; case 2: PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_GPIO2); break; case 4: PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO4_U, FUNC_GPIO4); break; case 5: PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO5_U, FUNC_GPIO5); break; default: break; } } /* Lua: ws2801.init(pin_clk, pin_data) * Sets up the GPIO pins * * ws2801.init(0, 2) uses GPIO0 as clock and GPIO2 as data. * This is the default behavior. */ static int ICACHE_FLASH_ATTR ws2801_init_lua(lua_State* L) { uint32_t pin_clk; uint32_t pin_data; uint32_t func_gpio_clk; uint32_t func_gpio_data; if (!lua_isnumber(L, 1) || !lua_isnumber(L, 2)) { // Use default pins if the input is omitted pin_clk = PIN_CLK_DEFAULT; pin_data = PIN_DATA_DEFAULT; } else { pin_clk = luaL_checkinteger(L, 1); pin_data = luaL_checkinteger(L, 2); } ws2801_bit_clk = 1 << pin_clk; ws2801_bit_data = 1 << pin_data; os_delay_us(10); //Set GPIO pins to output mode enable_pin_mux(pin_clk); enable_pin_mux(pin_data); //Set both GPIOs low low gpio_output_set(0, ws2801_bit_clk | ws2801_bit_data, ws2801_bit_clk | ws2801_bit_data, 0); os_delay_us(10); } /* Lua: ws2801.write(pin, "string") * Byte triples in the string are interpreted as R G B values. * This function does not corrupt your buffer. * * ws2801.write(string.char(255, 0, 0)) sets the first LED red. * ws2801.write(string.char(0, 0, 255):rep(10)) sets ten LEDs blue. * ws2801.write(string.char(0, 255, 0, 255, 255, 255)) first LED green, second LED white. */ static int ICACHE_FLASH_ATTR ws2801_writergb(lua_State* L) { size_t length; const char *buffer = luaL_checklstring(L, 1, &length); os_delay_us(10); ets_intr_lock(); ws2801_strip(buffer, length); ets_intr_unlock(); return 0; } static const LUA_REG_TYPE ws2801_map[] = { { LSTRKEY( "write" ), LFUNCVAL( ws2801_writergb )}, { LSTRKEY( "init" ), LFUNCVAL( ws2801_init_lua )}, { LNILKEY, LNILVAL} }; NODEMCU_MODULE(WS2801, "ws2801", ws2801_map, NULL);