obc_temperature_sensor.c File Reference

#include "main.h"
#include "stdio.h"
#include <stdint.h>
#include "obc_systems/obc_temperature_sensor.h"

Include dependency graph for obc_temperature_sensor.c:

Functions
uint8_t	OBC_TEMP_SENSOR_read_temperature (int32_t *result)
	Reads the temperature from the STDS75DS2F and stores it in the provided variable pointer result. Precision can be configured from 9 to 12 bits. Temperature range is -55 to 125 degrees celsius with +/- 3 degrees celsius over the whole range.
int32_t	OBC_TEMP_SENSOR_convert_raw_to_deg_c (uint8_t raw_bytes[], uint8_t precision_coefficient, Temperature_Sensor_Data_Precision_Insignificant_Bytes_t precision_insignificant_bits, uint16_t precision_scaling_factor)
	Converts the raw bytes provided to a temperature in celsius and multiplied by a scaling factor based on the provided precision. Works on the four MSBs. Reference https://www.st.com/resource/en/datasheet/stds75.pdf page 15 and 18 for information on calculations and format of temperature data.
int8_t	OBC_TEMP_SENSOR_get_temp_precision ()
	Reads the temperature precision from the config register. Refer to https://www.st.com/resource/en/datasheet/stds75.pdf page 17, table 6 and 7 for more information.
uint8_t	OBC_TEMP_SENSOR_set_temp_precision (uint8_t arg_precision, uint32_t *temp_precision_conversion_delay_ms, uint32_t *temp_scaling_factor)
	Set the temp temperature precision in the config register.
uint8_t	OBC_TEMP_SENSOR_configure_precision_values (uint8_t arg_precision, struct Set_Precision_Data *precision_data)
	Configures the precision global variables in preparation for setting the precision.
int32_t	OBC_TEMP_SENSOR_get_temperature_cC ()
	The simplest and most foolproof way to get the OBC temperature in centi-celsius.

Variables
const uint16_t	OBC_TEMP_SENSOR_device_addr = 0x48
const uint16_t	OBC_TEMP_SENSOR_temp_register_addr = 0x00
const uint32_t	OBC_TEMP_SENSOR_timeout_ms = 50
const uint16_t	OBC_TEMP_SENSOR_config_register_addr = 0x01
const uint8_t	OBC_TEMP_SENSOR_precision = 0x01 << 5
uint16_t	OBC_TEMP_SENSOR_precision_scaling_factor = 100
float	OBC_TEMP_SENSOR_precision_coefficient = OBC_TEMP_SENSOR_ten_bit_precision_coefficient
Temperature_Sensor_Data_Precision_Insignificant_Bytes_t	OBC_TEMP_SENSOR_precision_insignificant_bits = OBC_TEMP_SENSOR_TEN_BIT_PRECISION_INSIGNIFICANT_BYTES

Function Documentation

OBC_TEMP_SENSOR_configure_precision_values()

uint8_t OBC_TEMP_SENSOR_configure_precision_values	(	uint8_t	arg_precision,
		struct Set_Precision_Data *	precision_data )

Configures the precision global variables in preparation for setting the precision.

Parameters

arg_precision	precision to set the temperature to in decimal (9, 10, 11, 12).
precision_data	struct containing all the values needed in precision calculations.

Returns

0 on success, 1 if user passed in an invalid precision value.

Here is the caller graph for this function:

OBC_TEMP_SENSOR_convert_raw_to_deg_c()

int32_t OBC_TEMP_SENSOR_convert_raw_to_deg_c	(	uint8_t	raw_bytes[],
		uint8_t	precision_coefficient,
		Temperature_Sensor_Data_Precision_Insignificant_Bytes_t	precision_insignificant_bits,
		uint16_t	precision_scaling_factor )

Converts the raw bytes provided to a temperature in celsius and multiplied by a scaling factor based on the provided precision. Works on the four MSBs. Reference https://www.st.com/resource/en/datasheet/stds75.pdf page 15 and 18 for information on calculations and format of temperature data.

Parameters

raw_bytes	Bytes to convert to celsius float value
TEMP_SENSOR_data_precision_coefficient	Coefficient used to get the temperature in the correct precision.
TEMP_SENSOR_data_precision_insignificant_bits	Value used to remove always zero bits and bits not used the provided precision.
precision_scaling_factor	Value used to convert the temperature into a representation with no fractional parts.

Returns

the temperature in celsius after conversion.

Here is the caller graph for this function:

OBC_TEMP_SENSOR_get_temp_precision()

int8_t OBC_TEMP_SENSOR_get_temp_precision

(

void

)

Reads the temperature precision from the config register. Refer to https://www.st.com/resource/en/datasheet/stds75.pdf page 17, table 6 and 7 for more information.

Parameters

None

Returns

-1 if there is an error otherwise the temperature precision in the least significant two bits as 0x01, 0x02, 0x03, 0x04.

OBC_TEMP_SENSOR_get_temperature_cC()

int32_t OBC_TEMP_SENSOR_get_temperature_cC

(

)

The simplest and most foolproof way to get the OBC temperature in centi-celsius.

Returns

The temperature in cC, if successful. 99999 (OBC_TEMP_SENSOR_ERROR_TEMPERATURE_CC) if unsuccessful.

Here is the call graph for this function:

Here is the caller graph for this function:

OBC_TEMP_SENSOR_read_temperature()

uint8_t OBC_TEMP_SENSOR_read_temperature

(

int32_t *

result

)

Reads the temperature from the STDS75DS2F and stores it in the provided variable pointer result. Precision can be configured from 9 to 12 bits. Temperature range is -55 to 125 degrees celsius with +/- 3 degrees celsius over the whole range.

Parameters

result

Memory location to store the temperature result (units: degrees celsius).

Returns

0 if successful, 1 if config register error, 2 if temp register error.

Note

You may think this gets you the temperature in cC, but it doesn't!!

Here is the call graph for this function:

Here is the caller graph for this function:

OBC_TEMP_SENSOR_set_temp_precision()

uint8_t OBC_TEMP_SENSOR_set_temp_precision	(	uint8_t	arg_precision,
		uint32_t *	temp_precision_conversion_delay_ms,
		uint32_t *	temp_scaling_factor )

Set the temp temperature precision in the config register.

Parameters

arg_precision	Precision to set the temperature to in decimal (9, 10, 11, 12).
temp_precision_conversion_delay_ms	Pointer to store the conversion delay.
temp_scaling_factor	Pointer to store the scaling factor.

Returns

0 on success, 1 on write error, 2 when passed an invalid precision value.

Here is the call graph for this function:

Here is the caller graph for this function:

Variable Documentation

OBC_TEMP_SENSOR_config_register_addr

const uint16_t OBC_TEMP_SENSOR_config_register_addr = 0x01

OBC_TEMP_SENSOR_device_addr

const uint16_t OBC_TEMP_SENSOR_device_addr = 0x48

OBC_TEMP_SENSOR_precision

const uint8_t OBC_TEMP_SENSOR_precision = 0x01 << 5

OBC_TEMP_SENSOR_precision_coefficient

float OBC_TEMP_SENSOR_precision_coefficient = OBC_TEMP_SENSOR_ten_bit_precision_coefficient

OBC_TEMP_SENSOR_precision_insignificant_bits

Temperature_Sensor_Data_Precision_Insignificant_Bytes_t OBC_TEMP_SENSOR_precision_insignificant_bits = OBC_TEMP_SENSOR_TEN_BIT_PRECISION_INSIGNIFICANT_BYTES

OBC_TEMP_SENSOR_precision_scaling_factor

uint16_t OBC_TEMP_SENSOR_precision_scaling_factor = 100

OBC_TEMP_SENSOR_temp_register_addr

const uint16_t OBC_TEMP_SENSOR_temp_register_addr = 0x00

OBC_TEMP_SENSOR_timeout_ms

const uint32_t OBC_TEMP_SENSOR_timeout_ms = 50