Adding support for MAX31856 Thermocouple Temperature Sensor (feature #700) (#1039)

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declanshanaghy 2020-05-24 15:33:59 -07:00 committed by GitHub
parent fb2b7ade41
commit e64246f642
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7 changed files with 330 additions and 1 deletions

1
.gitignore vendored
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@ -51,6 +51,7 @@ htmlcov/
.coverage
.coverage.*
.cache
.esphome
nosetests.xml
coverage.xml
*.cover

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#include "max31856.h"
#include "esphome/core/log.h"
#include <cmath>
namespace esphome {
namespace max31856 {
static const char *TAG = "max31856";
// Based on Adafruit's library: https://github.com/adafruit/Adafruit_MAX31856
void MAX31856Sensor::setup() {
ESP_LOGCONFIG(TAG, "Setting up MAX31856Sensor '%s'...", this->name_.c_str());
this->spi_setup();
// assert on any fault
ESP_LOGCONFIG(TAG, "Setting up assertion on all faults");
this->write_register_(MAX31856_MASK_REG, 0x0);
ESP_LOGCONFIG(TAG, "Setting up open circuit fault detection");
this->write_register_(MAX31856_CR0_REG, MAX31856_CR0_OCFAULT01);
this->set_thermocouple_type_();
this->set_noise_filter_();
ESP_LOGCONFIG(TAG, "Completed setting up MAX31856Sensor '%s'...", this->name_.c_str());
}
void MAX31856Sensor::dump_config() {
LOG_SENSOR("", "MAX31856", this);
LOG_PIN(" CS Pin: ", this->cs_);
ESP_LOGCONFIG(TAG, " Mains Filter: %s",
(filter_ == FILTER_60HZ ? "60 Hz" : (filter_ == FILTER_50HZ ? "50 Hz" : "Unknown!")));
LOG_UPDATE_INTERVAL(this);
}
void MAX31856Sensor::update() {
ESP_LOGVV(TAG, "update");
this->one_shot_temperature_();
// Datasheet max conversion time for 1 shot is 155ms for 60Hz / 185ms for 50Hz
auto f = std::bind(&MAX31856Sensor::read_thermocouple_temperature_, this);
this->set_timeout("MAX31856Sensor::read_thermocouple_temperature_", filter_ == FILTER_60HZ ? 155 : 185, f);
}
void MAX31856Sensor::read_thermocouple_temperature_() {
if (this->has_fault_()) {
// Faults have been logged, clear it for next loop
this->clear_fault_();
} else {
int32_t temp24 = this->read_register24_(MAX31856_LTCBH_REG);
if (temp24 & 0x800000) {
temp24 |= 0xFF000000; // fix sign
}
temp24 >>= 5; // bottom 5 bits are unused
float temp_c = temp24;
temp_c *= 0.0078125;
ESP_LOGD(TAG, "Got thermocouple temperature: %.2f°C", temp_c);
this->publish_state(temp_c);
}
}
void MAX31856Sensor::one_shot_temperature_() {
ESP_LOGVV(TAG, "one_shot_temperature_");
this->write_register_(MAX31856_CJTO_REG, 0x0);
uint8_t t = this->read_register_(MAX31856_CR0_REG);
t &= ~MAX31856_CR0_AUTOCONVERT; // turn off autoconversion mode
t |= MAX31856_CR0_1SHOT; // turn on one shot mode
this->write_register_(MAX31856_CR0_REG, t);
}
bool MAX31856Sensor::has_fault_() {
ESP_LOGVV(TAG, "read_fault_");
uint8_t faults = this->read_register_(MAX31856_SR_REG);
if (faults == 0) {
ESP_LOGV(TAG, "status_set_warning");
this->status_clear_warning();
return false;
}
ESP_LOGV(TAG, "status_set_warning");
this->status_set_warning();
if ((faults & MAX31856_FAULT_CJRANGE) == MAX31856_FAULT_CJRANGE) {
ESP_LOGW(TAG, "Cold Junction Out-of-Range: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_TCRANGE) == MAX31856_FAULT_TCRANGE) {
ESP_LOGW(TAG, "Thermocouple Out-of-Range: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_CJHIGH) == MAX31856_FAULT_CJHIGH) {
ESP_LOGW(TAG, "Cold-Junction High Fault: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_CJLOW) == MAX31856_FAULT_CJLOW) {
ESP_LOGW(TAG, "Cold-Junction Low Fault: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_TCHIGH) == MAX31856_FAULT_TCHIGH) {
ESP_LOGW(TAG, "Thermocouple Temperature High Fault: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_TCLOW) == MAX31856_FAULT_TCLOW) {
ESP_LOGW(TAG, "Thermocouple Temperature Low Fault: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_OVUV) == MAX31856_FAULT_OVUV) {
ESP_LOGW(TAG, "Overvoltage or Undervoltage Input Fault: '%s'...", this->name_.c_str());
}
if ((faults & MAX31856_FAULT_OPEN) == MAX31856_FAULT_OPEN) {
ESP_LOGW(TAG, "Thermocouple Open-Circuit Fault (possibly not connected): '%s'...", this->name_.c_str());
}
return true;
}
void MAX31856Sensor::clear_fault_() {
ESP_LOGV(TAG, "clear_fault_");
uint8_t t = this->read_register_(MAX31856_CR0_REG);
t |= MAX31856_CR0_FAULT; // turn on fault interrupt mode
t |= MAX31856_CR0_FAULTCLR; // enable the fault status clear bit
this->write_register_(MAX31856_CR0_REG, t);
}
void MAX31856Sensor::set_thermocouple_type_() {
MAX31856ThermocoupleType type = MAX31856_TCTYPE_K;
ESP_LOGCONFIG(TAG, "set_thermocouple_type_: 0x%02X", type);
uint8_t t = this->read_register_(MAX31856_CR1_REG);
t &= 0xF0; // mask off bottom 4 bits
t |= (uint8_t) type & 0x0F;
this->write_register_(MAX31856_CR1_REG, t);
}
void MAX31856Sensor::set_noise_filter_() {
ESP_LOGCONFIG(TAG, "set_noise_filter_: 0x%02X", filter_);
uint8_t t = this->read_register_(MAX31856_CR0_REG);
if (filter_ == FILTER_50HZ) {
t |= 0x01;
ESP_LOGCONFIG(TAG, "set_noise_filter_: 50 Hz, t==0x%02X", t);
} else {
t &= 0xfe;
ESP_LOGCONFIG(TAG, "set_noise_filter_: 60 Hz, t==0x%02X", t);
}
this->write_register_(MAX31856_CR0_REG, t);
}
void MAX31856Sensor::write_register_(uint8_t reg, uint8_t value) {
ESP_LOGVV(TAG, "write_register_ raw reg=0x%02X value=0x%02X", reg, value);
reg |= SPI_WRITE_M;
ESP_LOGVV(TAG, "write_register_ masked reg=0x%02X value=0x%02X", reg, value);
this->enable();
ESP_LOGVV(TAG, "write_byte reg=0x%02X", reg);
this->write_byte(reg);
ESP_LOGVV(TAG, "write_byte value=0x%02X", value);
this->write_byte(value);
this->disable();
ESP_LOGV(TAG, "write_register_ 0x%02X: 0x%02X", reg, value);
}
const uint8_t MAX31856Sensor::read_register_(uint8_t reg) {
ESP_LOGVV(TAG, "read_register_ 0x%02X", reg);
this->enable();
ESP_LOGVV(TAG, "write_byte reg=0x%02X", reg);
this->write_byte(reg);
const uint8_t value(this->read_byte());
ESP_LOGVV(TAG, "read_byte value=0x%02X", value);
this->disable();
ESP_LOGV(TAG, "read_register_ reg=0x%02X: value=0x%02X", reg, value);
return value;
}
const uint32_t MAX31856Sensor::read_register24_(uint8_t reg) {
ESP_LOGVV(TAG, "read_register_24_ 0x%02X", reg);
this->enable();
ESP_LOGVV(TAG, "write_byte reg=0x%02X", reg);
this->write_byte(reg);
const uint8_t msb(this->read_byte());
ESP_LOGVV(TAG, "read_byte msb=0x%02X", msb);
const uint8_t mid(this->read_byte());
ESP_LOGVV(TAG, "read_byte mid=0x%02X", mid);
const uint8_t lsb(this->read_byte());
ESP_LOGVV(TAG, "read_byte lsb=0x%02X", lsb);
this->disable();
const uint32_t value((msb << 16) | (mid << 8) | lsb);
ESP_LOGV(TAG, "read_register_24_ reg=0x%02X: value=0x%06X", reg, value);
return value;
}
float MAX31856Sensor::get_setup_priority() const { return setup_priority::DATA; }
} // namespace max31856
} // namespace esphome

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#pragma once
#include "esphome/components/sensor/sensor.h"
#include "esphome/components/spi/spi.h"
#include "esphome/core/component.h"
namespace esphome {
namespace max31856 {
enum MAX31856RegisterMasks { SPI_WRITE_M = 0x80 };
enum MAX31856Registers {
MAX31856_CR0_REG = 0x00, ///< Config 0 register
MAX31856_CR0_AUTOCONVERT = 0x80, ///< Config 0 Auto convert flag
MAX31856_CR0_1SHOT = 0x40, ///< Config 0 one shot convert flag
MAX31856_CR0_OCFAULT00 = 0x00, ///< Config 0 open circuit fault 00 flag
MAX31856_CR0_OCFAULT01 = 0x10, ///< Config 0 open circuit fault 01 flag
MAX31856_CR0_OCFAULT10 = 0x20, ///< Config 0 open circuit fault 10 flag
MAX31856_CR0_CJ = 0x08, ///< Config 0 cold junction disable flag
MAX31856_CR0_FAULT = 0x04, ///< Config 0 fault mode flag
MAX31856_CR0_FAULTCLR = 0x02, ///< Config 0 fault clear flag
MAX31856_CR1_REG = 0x01, ///< Config 1 register
MAX31856_MASK_REG = 0x02, ///< Fault Mask register
MAX31856_CJHF_REG = 0x03, ///< Cold junction High temp fault register
MAX31856_CJLF_REG = 0x04, ///< Cold junction Low temp fault register
MAX31856_LTHFTH_REG = 0x05, ///< Linearized Temperature High Fault Threshold Register, MSB
MAX31856_LTHFTL_REG = 0x06, ///< Linearized Temperature High Fault Threshold Register, LSB
MAX31856_LTLFTH_REG = 0x07, ///< Linearized Temperature Low Fault Threshold Register, MSB
MAX31856_LTLFTL_REG = 0x08, ///< Linearized Temperature Low Fault Threshold Register, LSB
MAX31856_CJTO_REG = 0x09, ///< Cold-Junction Temperature Offset Register
MAX31856_CJTH_REG = 0x0A, ///< Cold-Junction Temperature Register, MSB
MAX31856_CJTL_REG = 0x0B, ///< Cold-Junction Temperature Register, LSB
MAX31856_LTCBH_REG = 0x0C, ///< Linearized TC Temperature, Byte 2
MAX31856_LTCBM_REG = 0x0D, ///< Linearized TC Temperature, Byte 1
MAX31856_LTCBL_REG = 0x0E, ///< Linearized TC Temperature, Byte 0
MAX31856_SR_REG = 0x0F, ///< Fault Status Register
MAX31856_FAULT_CJRANGE = 0x80, ///< Fault status Cold Junction Out-of-Range flag
MAX31856_FAULT_TCRANGE = 0x40, ///< Fault status Thermocouple Out-of-Range flag
MAX31856_FAULT_CJHIGH = 0x20, ///< Fault status Cold-Junction High Fault flag
MAX31856_FAULT_CJLOW = 0x10, ///< Fault status Cold-Junction Low Fault flag
MAX31856_FAULT_TCHIGH = 0x08, ///< Fault status Thermocouple Temperature High Fault flag
MAX31856_FAULT_TCLOW = 0x04, ///< Fault status Thermocouple Temperature Low Fault flag
MAX31856_FAULT_OVUV = 0x02, ///< Fault status Overvoltage or Undervoltage Input Fault flag
MAX31856_FAULT_OPEN = 0x01, ///< Fault status Thermocouple Open-Circuit Fault flag
};
/**
* Multiple types of thermocouples supported by the chip.
* Currently only K type implemented here.
*/
enum MAX31856ThermocoupleType {
MAX31856_TCTYPE_B = 0b0000, // 0x00
MAX31856_TCTYPE_E = 0b0001, // 0x01
MAX31856_TCTYPE_J = 0b0010, // 0x02
MAX31856_TCTYPE_K = 0b0011, // 0x03
MAX31856_TCTYPE_N = 0b0100, // 0x04
MAX31856_TCTYPE_R = 0b0101, // 0x05
MAX31856_TCTYPE_S = 0b0110, // 0x06
MAX31856_TCTYPE_T = 0b0111, // 0x07
MAX31856_VMODE_G8 = 0b1000, // 0x08
MAX31856_VMODE_G32 = 0b1100, // 0x12
};
enum MAX31856ConfigFilter {
FILTER_60HZ = 0,
FILTER_50HZ = 1,
};
class MAX31856Sensor : public sensor::Sensor,
public PollingComponent,
public spi::SPIDevice<spi::BIT_ORDER_MSB_FIRST, spi::CLOCK_POLARITY_LOW,
spi::CLOCK_PHASE_TRAILING, spi::DATA_RATE_4MHZ> {
public:
void setup() override;
void dump_config() override;
float get_setup_priority() const override;
void set_filter(MAX31856ConfigFilter filter) { filter_ = filter; }
void update() override;
protected:
MAX31856ConfigFilter filter_;
const uint8_t read_register_(uint8_t reg);
const uint32_t read_register24_(uint8_t reg);
void write_register_(uint8_t reg, uint8_t value);
void one_shot_temperature_();
bool has_fault_();
void clear_fault_();
void read_thermocouple_temperature_();
void set_thermocouple_type_();
void set_noise_filter_();
};
} // namespace max31856
} // namespace esphome

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import esphome.codegen as cg
import esphome.config_validation as cv
from esphome.components import sensor, spi
from esphome.const import CONF_ID, CONF_MAINS_FILTER, ICON_THERMOMETER, UNIT_CELSIUS
max31856_ns = cg.esphome_ns.namespace('max31856')
MAX31856Sensor = max31856_ns.class_('MAX31856Sensor', sensor.Sensor, cg.PollingComponent,
spi.SPIDevice)
MAX31865ConfigFilter = max31856_ns.enum('MAX31856ConfigFilter')
FILTER = {
'50HZ': MAX31865ConfigFilter.FILTER_50HZ,
'60HZ': MAX31865ConfigFilter.FILTER_60HZ,
}
CONFIG_SCHEMA = sensor.sensor_schema(UNIT_CELSIUS, ICON_THERMOMETER, 1).extend({
cv.GenerateID(): cv.declare_id(MAX31856Sensor),
cv.Optional(CONF_MAINS_FILTER, default='60HZ'): cv.enum(FILTER, upper=True, space=''),
}).extend(cv.polling_component_schema('60s')).extend(spi.SPI_DEVICE_SCHEMA)
def to_code(config):
var = cg.new_Pvariable(config[CONF_ID])
yield cg.register_component(var, config)
yield spi.register_spi_device(var, config)
yield sensor.register_sensor(var, config)
cg.add(var.set_filter(config[CONF_MAINS_FILTER]))

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@ -83,7 +83,7 @@ void MAX31865Sensor::dump_config() {
LOG_UPDATE_INTERVAL(this);
ESP_LOGCONFIG(TAG, " Reference Resistance: %.2fΩ", reference_resistance_);
ESP_LOGCONFIG(TAG, " RTD: %u-wire %.2fΩ", rtd_wires_, rtd_nominal_resistance_);
ESP_LOGCONFIG(TAG, " Filter: %s",
ESP_LOGCONFIG(TAG, " Mains Filter: %s",
(filter_ == FILTER_60HZ ? "60 Hz" : (filter_ == FILTER_50HZ ? "50 Hz" : "Unknown!")));
}

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@ -498,6 +498,11 @@ sensor:
update_interval: 15s
reference_temperature:
name: "MAX31855 Internal Temperature"
- platform: max31856
name: "BBQ Temperature"
cs_pin: GPIO17
update_interval: 15s
mains_filter: 50Hz
- platform: max31865
name: "Water Tank Temperature"
cs_pin: GPIO23