Tasmota/tasmota/xsns_41_max44009.ino

171 lines
4.8 KiB
C++

/*
xsns_41_max44009.ino - MAX44009 ambient light sensor support for Tasmota
Copyright (C) 2019 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 <http://www.gnu.org/licenses/>.
*/
#ifdef USE_I2C
#ifdef USE_MAX44009
/*********************************************************************************************\
* MAX44009 - Ambient Light Intensity
*
* I2C Address: 0x4a or 0x4b
\*********************************************************************************************/
#define XSNS_41 41
#define XI2C_28 28 // See I2CDEVICES.md
#define MAX44009_ADDR1 0x4A
#define MAX44009_ADDR2 0x4B
#define MAX44009_NO_REGISTERS 8
#define REG_CONFIG 0x02
#define REG_LUMINANCE 0x03
#define REG_LOWER_THRESHOLD 0x06
#define REG_THRESHOLD_TIMER 0x07
#define MAX44009_CONTINUOUS_AUTO_MODE 0x80 // Start measurement in automatic, continous mode
uint8_t max44009_address;
uint8_t max44009_addresses[] = { MAX44009_ADDR1, MAX44009_ADDR2, 0 }; //0 terminated list
uint8_t max44009_found = 0;
uint8_t max44009_valid = 0;
float max44009_illuminance = 0;
char max44009_types[] = "MAX44009";
bool Max4409Read_lum(void)
{
max44009_valid = 0;
uint8_t regdata[2];
/* Read 2 bytes luminance */
if (I2cValidRead16((uint16_t *)&regdata, max44009_address, REG_LUMINANCE)) {
int exponent = (regdata[0] & 0xF0) >> 4;
int mantissa = ((regdata[0] & 0x0F) << 4) | (regdata[1] & 0x0F);
max44009_illuminance = (float)(((0x00000001 << exponent) * (float)mantissa) * 0.045);
max44009_valid = 1;
return true;
} else {
return false;
}
}
/********************************************************************************************/
void Max4409Detect(void)
{
uint8_t buffer1;
uint8_t buffer2;
for (uint32_t i = 0; 0 != max44009_addresses[i]; i++) {
max44009_address = max44009_addresses[i];
if (I2cActive(max44009_address)) { continue; }
if ((I2cValidRead8(&buffer1, max44009_address, REG_LOWER_THRESHOLD)) &&
(I2cValidRead8(&buffer2, max44009_address, REG_THRESHOLD_TIMER))) {
//AddLog_P2(LOG_LEVEL_DEBUG_MORE, PSTR("MAX44009 %x: %x, %x"), max44009_address, (int)buffer1, (int)buffer2);
if ((0x00 == buffer1) &&
(0xFF == buffer2)) {
// looks like a MAX44009, try to initialize
Wire.beginTransmission(max44009_address);
// select configuration register and set mode
Wire.write(REG_CONFIG);
Wire.write(MAX44009_CONTINUOUS_AUTO_MODE);
if (0 == Wire.endTransmission()) {
I2cSetActiveFound(max44009_address, max44009_types);
max44009_found = 1;
break;
}
}
}
}
}
void Max4409EverySecond(void)
{
Max4409Read_lum();
}
void Max4409Show(bool json)
{
char illum_str[8];
if (max44009_valid) {
/* convert illuminance to string with suitable accuracy */
uint8_t prec = 0;
if (10 > max44009_illuminance ) {
prec = 3;
} else if (100 > max44009_illuminance) {
prec = 2;
} else if (1000 > max44009_illuminance) {
prec = 1;
}
dtostrf(max44009_illuminance, sizeof(illum_str) -1, prec, illum_str);
if (json) {
ResponseAppend_P(PSTR(",\"%s\":{\"" D_JSON_ILLUMINANCE "\":%s}"), max44009_types, illum_str);
#ifdef USE_DOMOTICZ
if (0 == tele_period) {
DomoticzSensor(DZ_ILLUMINANCE, illum_str);
}
#endif // USE_DOMOTICZ
#ifdef USE_WEBSERVER
} else {
// show integer value for lx on web-server
WSContentSend_PD(HTTP_SNS_ILLUMINANCE, max44009_types, (int)max44009_illuminance);
#endif // USE_WEBSERVER
}
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns41(uint8_t function)
{
if (!I2cEnabled(XI2C_28)) { return false; }
bool result = false;
if (FUNC_INIT == function) {
Max4409Detect();
}
else if (max44009_found) {
switch (function) {
case FUNC_EVERY_SECOND:
Max4409EverySecond();
break;
case FUNC_JSON_APPEND:
Max4409Show(1);
break;
#ifdef USE_WEBSERVER
case FUNC_WEB_SENSOR:
Max4409Show(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_MAX44009
#endif // USE_I2C