add ds18b20 module (#2003)

* add ds18b20 module
* add intitial eeprom value definition
* adjust read() function and address handling

Author: fetchbot

app/include/user_modules.h

@@ -29,6 +29,7 @@
 //#define LUA_USE_MODULES_CRON
 //#define LUA_USE_MODULES_CRYPTO
 #define LUA_USE_MODULES_DHT
+//#define LUA_USE_MODULES_DS18B20
 //#define LUA_USE_MODULES_ENCODER
 //#define LUA_USE_MODULES_ENDUSER_SETUP // USE_DNS in dhcpserver.h needs to be enabled for this module to work.
 #define LUA_USE_MODULES_FILE

app/modules/ds18b20.c

@@ -0,0 +1,295 @@
+//***************************************************************************
+// DS18B20 module for ESP8266 with nodeMCU
+// fetchbot @github
+// MIT license, http://opensource.org/licenses/MIT
+//***************************************************************************
+
+#include "module.h"
+#include "lauxlib.h"
+#include "platform.h"
+#include "osapi.h"
+#include "driver/onewire.h"
+#include "c_stdio.h"
+#include "c_stdlib.h"
+
+//***************************************************************************
+// OW ROM COMMANDS
+//***************************************************************************
+
+#define DS18B20_ROM_SEARCH				(0xF0)
+#define DS18B20_ROM_READ				(0x33)
+#define DS18B20_ROM_MATCH				(0x55)
+#define DS18B20_ROM_SKIP				(0xCC)
+#define DS18B20_ROM_SEARCH_ALARM		(0xEC)
+
+//***************************************************************************
+// OW FUNCTION COMMANDS
+//***************************************************************************
+
+#define DS18B20_FUNC_CONVERT			(0x44)
+#define DS18B20_FUNC_SCRATCH_WRITE		(0x4E)
+#define DS18B20_FUNC_SCRATCH_READ		(0xBE)
+#define DS18B20_FUNC_SCRATCH_COPY		(0x48)
+#define DS18B20_FUNC_E2_RECALL			(0xB8)
+#define DS18B20_FUNC_POWER_READ			(0xB4)
+
+//***************************************************************************
+// Initial EEPROM values
+//***************************************************************************
+
+#define DS18B20_EEPROM_TH				(0x4B)		// 75 degree
+#define DS18B20_EEPROM_TL				(0x46)		// 70 degree
+#define DS18B20_EEPROM_RES				(0x7F)		// 12 bit resolution
+
+//***************************************************************************
+
+static uint8_t ds18b20_bus_pin;
+static uint8_t ds18b20_device_family;
+static uint8_t ds18b20_device_search = 0;
+static uint8_t ds18b20_device_index;
+static uint8_t ds18b20_device_par;
+static uint8_t ds18b20_device_conf[3];
+static uint8_t ds18b20_device_rom[8];
+static uint8_t ds18b20_device_scratchpad[9];
+static double ds18b20_device_scratchpad_temp;
+static int ds18b20_device_scratchpad_temp_dec;
+static uint8_t ds18b20_device_scratchpad_conf;
+static uint8_t ds18b20_device_res = 12;			// 12 bit resolution (750ms conversion time)
+
+os_timer_t ds18b20_timer;						// timer for conversion delay
+int ds18b20_timer_ref;							// callback when readout is ready
+
+int ds18b20_table_ref;
+static int ds18b20_table_offset;
+
+static int ds18b20_lua_readoutdone(void);
+
+// Setup onewire bus for DS18B20 temperature sensors
+// Lua: ds18b20.setup(OW_BUS_PIN)
+static int ds18b20_lua_setup(lua_State *L) {
+	// check ow bus pin value
+	if (!lua_isnumber(L, 1) || lua_isnumber(L, 1) == 0) {
+		return luaL_error(L, "wrong 1-wire pin");
+	}
+	
+	ds18b20_bus_pin = luaL_checkinteger(L, 1);
+	MOD_CHECK_ID(ow, ds18b20_bus_pin);
+	onewire_init(ds18b20_bus_pin);
+}
+
+static int ds18b20_set_device(uint8_t *ds18b20_device_rom) {
+	onewire_reset(ds18b20_bus_pin);
+	onewire_select(ds18b20_bus_pin, ds18b20_device_rom);
+	onewire_write(ds18b20_bus_pin, DS18B20_FUNC_SCRATCH_WRITE, 0);
+	onewire_write_bytes(ds18b20_bus_pin, ds18b20_device_conf, 3, 0);
+}
+
+// Change sensor settings
+// Lua: ds18b20.setting(ROM, RES)
+static int ds18b20_lua_setting(lua_State *L) {
+	// check rom table and resolution setting
+	if (!lua_istable(L, 1) || !lua_isnumber(L, 2)) {
+		return luaL_error(L, "wrong arg range");
+	}
+	
+	ds18b20_device_res = luaL_checkinteger(L, 2);
+	
+	if (!((ds18b20_device_res == 9) || (ds18b20_device_res == 10) || (ds18b20_device_res == 11) || (ds18b20_device_res == 12))) {
+		return luaL_error(L, "Invalid argument: resolution");
+	}
+	
+	// no change to th and tl setting
+	ds18b20_device_conf[0] = DS18B20_EEPROM_TH;
+	ds18b20_device_conf[1] = DS18B20_EEPROM_TL;
+	ds18b20_device_conf[2] = ((ds18b20_device_res - 9) << 5) + 0x1F;
+	
+	uint8_t table_len = lua_objlen(L, 1);
+	
+	const char *str[table_len];
+	const char *sep = ":";
+	
+	uint8_t string_index = 0;
+	
+	lua_pushnil(L);
+	while (lua_next(L, -3)) {
+		str[string_index] = lua_tostring(L, -1);
+		lua_pop(L, 1);
+		string_index++;
+	}
+	lua_pop(L, 1);
+	
+	for (uint8_t i = 0; i < string_index; i++) {
+		for (uint8_t j = 0; j < 8; j++) {
+			ds18b20_device_rom[j] = strtoul(str[i], NULL, 16);
+			str[i] = strchr(str[i], *sep);
+			if (str[i] == NULL || *str[i] == '\0') break;
+			str[i]++;
+		}
+		ds18b20_set_device(ds18b20_device_rom);
+	}
+	
+	// set conversion delay once to max if sensors with higher resolution still on the bus
+	ds18b20_device_res = 12;
+	
+	return 0;
+}
+
+// Reads sensor values from all devices
+// Lua: 	ds18b20.read(function(INDEX, ROM, RES, TEMP, TEMP_DEC, PAR) print(INDEX, ROM, RES, TEMP, TEMP_DEC, PAR) end, ROM[, FAMILY])
+static int ds18b20_lua_read(lua_State *L) {
+	
+	luaL_argcheck(L, (lua_type(L, 1) == LUA_TFUNCTION || lua_type(L, 1) == LUA_TLIGHTFUNCTION), 1, "Must be function");
+	
+	lua_pushvalue(L, 1);
+	ds18b20_timer_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+	
+	if (!lua_istable(L, 2)) {
+		return luaL_error(L, "wrong arg range");
+	}
+	
+	if (lua_isnumber(L, 3)) {
+		ds18b20_device_family = luaL_checkinteger(L, 3);
+		onewire_target_search(ds18b20_bus_pin, ds18b20_device_family);
+		ds18b20_table_offset = -3;
+	} else {
+		ds18b20_table_offset = -2;
+	}
+	
+	lua_pushvalue(L, 2);
+	ds18b20_table_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+	
+	lua_pushnil(L);
+	if (lua_next(L, ds18b20_table_offset)) {
+		lua_pop(L, 2);
+		ds18b20_device_search = 0;
+	} else {
+		ds18b20_device_search = 1;
+	}
+	
+	os_timer_disarm(&ds18b20_timer);
+	
+	// perform a temperature conversion for all sensors and set timer
+	onewire_reset(ds18b20_bus_pin);
+	onewire_write(ds18b20_bus_pin, DS18B20_ROM_SKIP, 0);
+	onewire_write(ds18b20_bus_pin, DS18B20_FUNC_CONVERT, 1);
+	os_timer_setfn(&ds18b20_timer, (os_timer_func_t *)ds18b20_lua_readoutdone, NULL);
+	
+	switch (ds18b20_device_res) {
+		case (9):
+			os_timer_arm(&ds18b20_timer, 95, 0);
+			break;
+		case (10):
+			os_timer_arm(&ds18b20_timer, 190, 0);
+			break;
+		case (11):
+			os_timer_arm(&ds18b20_timer, 380, 0);
+			break;
+		case (12):
+			os_timer_arm(&ds18b20_timer, 760, 0);
+			break;
+	}
+}
+
+static int ds18b20_read_device(uint8_t *ds18b20_device_rom) {
+	lua_State *L = lua_getstate();
+
+	if (onewire_crc8(ds18b20_device_rom,7) == ds18b20_device_rom[7]) {
+		
+		onewire_reset(ds18b20_bus_pin);
+		onewire_select(ds18b20_bus_pin, ds18b20_device_rom);
+		onewire_write(ds18b20_bus_pin, DS18B20_FUNC_POWER_READ, 0);
+		
+		if (onewire_read(ds18b20_bus_pin)) ds18b20_device_par = 0;
+		else ds18b20_device_par = 1;
+			
+		onewire_reset(ds18b20_bus_pin);
+		onewire_select(ds18b20_bus_pin, ds18b20_device_rom);
+		onewire_write(ds18b20_bus_pin, DS18B20_FUNC_SCRATCH_READ, 0);
+		onewire_read_bytes(ds18b20_bus_pin, ds18b20_device_scratchpad, 9);
+		
+		if (onewire_crc8(ds18b20_device_scratchpad,8) == ds18b20_device_scratchpad[8]) {
+			
+			lua_rawgeti(L, LUA_REGISTRYINDEX, ds18b20_timer_ref);
+			
+			lua_pushinteger(L, ds18b20_device_index);
+			
+			lua_pushfstring(L, "%d:%d:%d:%d:%d:%d:%d:%d", ds18b20_device_rom[0], ds18b20_device_rom[1], ds18b20_device_rom[2], ds18b20_device_rom[3], ds18b20_device_rom[4], ds18b20_device_rom[5], ds18b20_device_rom[6], ds18b20_device_rom[7]);
+			
+			ds18b20_device_scratchpad_conf = (ds18b20_device_scratchpad[4] >> 5) + 9;
+			ds18b20_device_scratchpad_temp = ((int8_t)(ds18b20_device_scratchpad[1] << 4) + (ds18b20_device_scratchpad[0] >> 4) + ((double)(ds18b20_device_scratchpad[0] & 0x0F) / 16));
+			ds18b20_device_scratchpad_temp_dec = ((double)(ds18b20_device_scratchpad[0] & 0x0F) / 16 * 1000);
+			
+			if (ds18b20_device_scratchpad_conf >= ds18b20_device_res) {
+				ds18b20_device_res = ds18b20_device_scratchpad_conf;
+			}
+			
+			lua_pushinteger(L, ds18b20_device_scratchpad_conf);
+			lua_pushnumber(L, ds18b20_device_scratchpad_temp);
+			lua_pushinteger(L, ds18b20_device_scratchpad_temp_dec);
+			
+			lua_pushinteger(L, ds18b20_device_par);
+			
+			lua_pcall(L, 6, 0, 0);
+			
+			ds18b20_device_index++;
+		}
+	}
+}
+
+static int ds18b20_lua_readoutdone(void) {
+	
+	lua_State *L = lua_getstate();
+	os_timer_disarm(&ds18b20_timer);
+	
+	ds18b20_device_index = 1;
+	// set conversion delay to min and change it after finding the sensor with the highest resolution setting
+	ds18b20_device_res = 9;
+	
+	if (ds18b20_device_search) {
+		// iterate through all sensors on the bus and read temperature, resolution and parasitc settings
+		while (onewire_search(ds18b20_bus_pin, ds18b20_device_rom)) {
+			ds18b20_read_device(ds18b20_device_rom);
+		}
+	} else {
+		lua_rawgeti(L, LUA_REGISTRYINDEX, ds18b20_table_ref);
+		uint8_t table_len = lua_objlen(L, -1);
+		
+		const char *str[table_len];
+		const char *sep = ":";
+		
+		uint8_t string_index = 0;
+		
+		lua_pushnil(L);
+		while (lua_next(L, -2)) {
+			str[string_index] = lua_tostring(L, -1);
+			lua_pop(L, 1);
+			string_index++;
+		}
+		lua_pop(L, 1);
+		
+		for (uint8_t i = 0; i < string_index; i++) {
+			for (uint8_t j = 0; j < 8; j++) {
+				ds18b20_device_rom[j] = strtoul(str[i], NULL, 16);
+				str[i] = strchr(str[i], *sep);
+				if (str[i] == NULL || *str[i] == '\0') break;
+				str[i]++;
+			}
+			ds18b20_read_device(ds18b20_device_rom);
+		}
+	}
+	
+	luaL_unref(L, LUA_REGISTRYINDEX, ds18b20_table_ref);
+	ds18b20_table_ref = LUA_NOREF;
+	
+	luaL_unref(L, LUA_REGISTRYINDEX, ds18b20_timer_ref);
+	ds18b20_timer_ref = LUA_NOREF;
+}
+
+static const LUA_REG_TYPE ds18b20_map[] = {
+	{	LSTRKEY( "read" ),				LFUNCVAL(ds18b20_lua_read)		},
+	{	LSTRKEY( "setting" ),			LFUNCVAL(ds18b20_lua_setting)	},
+	{	LSTRKEY( "setup" ),				LFUNCVAL(ds18b20_lua_setup)		},
+	{	LNILKEY, LNILVAL												}
+};
+
+NODEMCU_MODULE(DS18B20, "ds18b20", ds18b20_map, NULL);