max31865 - Driver for MAX31865 resistance converter for platinum RTDs¶
- group max31865
ESP-IDF driver for MAX31865, resistance converter for platinum RTDs.
Copyright (c) 2021 Ruslan V. Uss unclerus@gmail.com
BSD Licensed as described in the file LICENSE
Defines
-
MAX31865_MAX_CLOCK_SPEED_HZ¶
Enums
-
enum max31865_mode_t¶
Conversion mode.
Values:
-
enumerator MAX31865_MODE_SINGLE¶
Single consersion mode, default.
-
enumerator MAX31865_MODE_AUTO¶
Automatic conversion mode at 50/60Hz rate.
-
enumerator MAX31865_MODE_SINGLE¶
-
enum max31865_filter_t¶
Notch frequencies for the noise rejection filter.
Values:
-
enumerator MAX31865_FILTER_60HZ¶
60Hz
-
enumerator MAX31865_FILTER_50HZ¶
50Hz
-
enumerator MAX31865_FILTER_60HZ¶
Functions
-
esp_err_t max31865_init_desc(max31865_t *dev, spi_host_device_t host, uint32_t clock_speed_hz, gpio_num_t cs_pin)¶
Initialize device descriptor.
- Parameters
dev – Device descriptor
host – SPI host
clock_speed_hz – SPI clock speed, Hz
cs_pin – CS GPIO number
- Returns
ESP_OK
on success
-
esp_err_t max31865_free_desc(max31865_t *dev)¶
Free device descriptor.
- Parameters
dev – Device descriptor
- Returns
ESP_OK
on success
-
esp_err_t max31865_set_config(max31865_t *dev, const max31865_config_t *config)¶
Configure device.
- Parameters
dev – Device descriptor
config – Configuration
- Returns
ESP_OK
on success
-
esp_err_t max31865_get_config(max31865_t *dev, max31865_config_t *config)¶
Read device configuration.
- Parameters
dev – Device descriptor
config – [out] Configuration
- Returns
ESP_OK
on success
-
esp_err_t max31865_start_measurement(max31865_t *dev)¶
Trigger single-shot measurement.
- Parameters
dev – Device descriptor
- Returns
ESP_OK
on success
-
esp_err_t max31865_read_raw(max31865_t *dev, uint16_t *raw, bool *fault)¶
Read raw RTD value.
- Parameters
dev – Device descritptor
raw – [out] Raw 15 bits RTD value
fault – [out] true when fault is detected
- Returns
ESP_OK
on success
-
esp_err_t max31865_read_temperature(max31865_t *dev, float *temp)¶
Read RTD value and convert it temperature.
- Parameters
dev – Device descritptor
temp – [out] Temperature, deg. Celsius
- Returns
ESP_OK
on success
-
esp_err_t max31865_measure(max31865_t *dev, float *temp)¶
Measure temperature.
Run full cycle of single-shot measurement:
trigger measurement
wait for 70ms
read and convert RTD value
- Parameters
dev – Device descritptor
temp – [out] Temperature, deg. Celsius
- Returns
ESP_OK
on success
-
esp_err_t max31865_detect_fault_auto(max31865_t *dev)¶
Run automatical fault detection cycle.
After calling this function, device must be reconfigured
- Parameters
dev – Device descriptor
- Returns
ESP_OK
on success
-
esp_err_t max31865_get_fault_status(max31865_t *dev, uint8_t *fault_status)¶
Get bits of current fault status.
See datasheet for fault status interpretation
- Parameters
dev – Device descriptor
fault_status – [out] Fault status bits
- Returns
ESP_OK
on success
-
esp_err_t max31865_clear_fault_status(max31865_t *dev)¶
Clear current fault status.
After calling this function, device must be reconfigured
- Parameters
dev – Device descriptor
- Returns
ESP_OK
on success
-
struct max31865_config_t¶
- #include <max31865.h>
Device configuration.
-
struct max31865_t¶
- #include <max31865.h>
Device descriptor.
Public Members
-
spi_device_interface_config_t spi_cfg¶
SPI device configuration.
-
spi_device_handle_t spi_dev¶
SPI device handler.
-
max31865_standard_t standard¶
Temperature scale standard.
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float r_ref¶
Reference resistor value, Ohms.
-
float rtd_nominal¶
RTD nominal resistance at 0 deg.
C, Ohms (PT100 - 100 Ohms, PT1000 - 1000 Ohms)
-
spi_device_interface_config_t spi_cfg¶
-
MAX31865_MAX_CLOCK_SPEED_HZ¶