/*
xsns_05_ds18x20.ino - DS18x20 temperature sensor support for Sonoff-Tasmota
Copyright (C) 2017 Heiko Krupp and Theo Arends
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
#ifdef USE_DS18x20
/*********************************************************************************************\
* DS18B20 - Temperature
\*********************************************************************************************/
#define DS18S20_CHIPID 0x10
#define DS18B20_CHIPID 0x28
#define MAX31850_CHIPID 0x3B
#define W1_SKIP_ROM 0xCC
#define W1_CONVERT_TEMP 0x44
#define W1_READ_SCRATCHPAD 0xBE
#define DS18X20_MAX_SENSORS 8
#include
OneWire *ds = NULL;
uint8_t ds18x20_address[DS18X20_MAX_SENSORS][8];
uint8_t ds18x20_index[DS18X20_MAX_SENSORS];
uint8_t ds18x20_sensors = 0;
char ds18x20_types[9];
void Ds18x20Init()
{
ds = new OneWire(pin[GPIO_DSB]);
}
void Ds18x20Search()
{
uint8_t num_sensors=0;
uint8_t sensor = 0;
ds->reset_search();
for (num_sensors = 0; num_sensors < DS18X20_MAX_SENSORS; num_sensors) {
if (!ds->search(ds18x20_address[num_sensors])) {
ds->reset_search();
break;
}
// If CRC Ok and Type DS18S20, DS18B20 or MAX31850
if ((OneWire::crc8(ds18x20_address[num_sensors], 7) == ds18x20_address[num_sensors][7]) &&
((ds18x20_address[num_sensors][0]==DS18S20_CHIPID) || (ds18x20_address[num_sensors][0]==DS18B20_CHIPID) || (ds18x20_address[num_sensors][0]==MAX31850_CHIPID))) {
num_sensors++;
}
}
for (byte i = 0; i < num_sensors; i++) {
ds18x20_index[i] = i;
}
for (byte i = 0; i < num_sensors; i++) {
for (byte j = i + 1; j < num_sensors; j++) {
if (uint32_t(ds18x20_address[ds18x20_index[i]]) > uint32_t(ds18x20_address[ds18x20_index[j]])) {
std::swap(ds18x20_index[i], ds18x20_index[j]);
}
}
}
ds18x20_sensors = num_sensors;
}
uint8_t Ds18x20Sensors()
{
return ds18x20_sensors;
}
String Ds18x20Addresses(uint8_t sensor)
{
char address[20];
for (byte i = 0; i < 8; i++) {
sprintf(address+2*i, "%02X", ds18x20_address[ds18x20_index[sensor]][i]);
}
return String(address);
}
void Ds18x20Convert()
{
ds->reset();
ds->write(W1_SKIP_ROM); // Address all Sensors on Bus
ds->write(W1_CONVERT_TEMP); // start conversion, no parasite power on at the end
// delay(750); // 750ms should be enough for 12bit conv
}
boolean Ds18x20Read(uint8_t sensor, float &t)
{
byte data[12];
int8_t sign = 1;
float temp9 = 0.0;
uint8_t present = 0;
t = NAN;
ds->reset();
ds->select(ds18x20_address[ds18x20_index[sensor]]);
ds->write(W1_READ_SCRATCHPAD); // Read Scratchpad
for (byte i = 0; i < 9; i++) {
data[i] = ds->read();
}
if (OneWire::crc8(data, 8) == data[8]) {
switch(ds18x20_address[ds18x20_index[sensor]][0]) {
case DS18S20_CHIPID: // DS18S20
if (data[1] > 0x80) {
data[0] = (~data[0]) +1;
sign = -1; // App-Note fix possible sign error
}
if (data[0] & 1) {
temp9 = ((data[0] >> 1) + 0.5) * sign;
} else {
temp9 = (data[0] >> 1) * sign;
}
t = ConvertTemp((temp9 - 0.25) + ((16.0 - data[6]) / 16.0));
break;
case DS18B20_CHIPID: // DS18B20
case MAX31850_CHIPID: // MAX31850
uint16_t temp12 = (data[1] << 8) + data[0];
if (temp12 > 2047) {
temp12 = (~temp12) +1;
sign = -1;
}
t = ConvertTemp(sign * temp12 * 0.0625);
break;
}
}
return (!isnan(t));
}
/********************************************************************************************/
void Ds18x20Type(uint8_t sensor)
{
strcpy_P(ds18x20_types, PSTR("DS18x20"));
switch(ds18x20_address[ds18x20_index[sensor]][0]) {
case DS18S20_CHIPID:
strcpy_P(ds18x20_types, PSTR("DS18S20"));
break;
case DS18B20_CHIPID:
strcpy_P(ds18x20_types, PSTR("DS18B20"));
break;
case MAX31850_CHIPID:
strcpy_P(ds18x20_types, PSTR("MAX31850"));
break;
}
}
void Ds18x20Show(boolean json)
{
char temperature[10];
char stemp[10];
float t;
byte dsxflg = 0;
for (byte i = 0; i < Ds18x20Sensors(); i++) {
if (Ds18x20Read(i, t)) { // Check if read failed
Ds18x20Type(i);
dtostrfd(t, Settings.flag.temperature_resolution, temperature);
if (json) {
if (!dsxflg) {
snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s, \"DS18x20\":{"), mqtt_data);
stemp[0] = '\0';
}
dsxflg++;
snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s%s\"DS%d\":{\"" D_TYPE "\":\"%s\", \"" D_ADDRESS "\":\"%s\", \"" D_TEMPERATURE "\":%s}"),
mqtt_data, stemp, i +1, ds18x20_types, Ds18x20Addresses(i).c_str(), temperature);
strcpy(stemp, ", ");
#ifdef USE_DOMOTICZ
if (1 == dsxflg) {
DomoticzSensor(DZ_TEMP, temperature);
}
#endif // USE_DOMOTICZ
#ifdef USE_WEBSERVER
} else {
snprintf_P(stemp, sizeof(stemp), PSTR("%s-%d"), ds18x20_types, i +1);
snprintf_P(mqtt_data, sizeof(mqtt_data), HTTP_SNS_TEMP, mqtt_data, stemp, temperature, TempUnit());
#endif // USE_WEBSERVER
}
}
}
if (json) {
if (dsxflg) {
snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s}"), mqtt_data);
}
#ifdef USE_WEBSERVER
} else {
Ds18x20Search(); // Check for changes in sensors number
Ds18x20Convert(); // Start Conversion, takes up to one second
#endif // USE_WEBSERVER
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
#define XSNS_05
boolean Xsns05(byte function)
{
boolean result = false;
if (pin[GPIO_DSB] < 99) {
switch (function) {
case FUNC_XSNS_INIT:
Ds18x20Init();
break;
case FUNC_XSNS_PREP:
Ds18x20Search(); // Check for changes in sensors number
Ds18x20Convert(); // Start Conversion, takes up to one second
break;
case FUNC_XSNS_JSON_APPEND:
Ds18x20Show(1);
break;
#ifdef USE_WEBSERVER
case FUNC_XSNS_WEB:
Ds18x20Show(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_DS18x20