max6642.c File Reference

MAX6642 I2C Temperature Sensor Interface implementation. More...

#include "FreeRTOS.h"
#include "task.h"
#include "port.h"
#include "sdr.h"
#include "task_priorities.h"
#include "i2c.h"
#include "i2c_mapping.h"
#include "max6642.h"
#include "utils.h"
#include "uart_debug.h"

Include dependency graph for max6642.c:

Functions
void	vTaskMAX6642 (void *Parameters)
	MAX6642 Monitor Task.
void	MAX6642_init (void)
	Initializes MAX6642 sensor and creates vTaskMAX6642.
Bool	max6642_read_local (sensor_t *sensor, uint8_t *temp)
	Reads MAX6642's local temperature value.
Bool	max6642_read_remote (sensor_t *sensor, uint8_t *temp)
	Reads MAX6642's remote temperature value.
Bool	max6642_read_local_extd (sensor_t *sensor, uint8_t *temp)
	Reads MAX6642's local extended temperature value.
Bool	max6642_read_remote_extd (sensor_t *sensor, uint8_t *temp)
	Reads MAX6642's remote extended temperature value.
uint8_t	max6642_read_status (sensor_t *sensor)
	Reads MAX6642 status byte.
uint8_t	max6642_read_cfg (sensor_t *sensor)
	Reads MAX6642 configuration byte.
void	max6642_write_cfg (sensor_t *sensor, uint8_t cfg)
	Writes MAX6642 configuration byte.
void	max6642_write_local_limit (sensor_t *sensor, uint8_t limit)
	Sets internal high temperature limit that asserts 'ALERT.
void	max6642_write_remote_limit (sensor_t *sensor, uint8_t limit)
	Sets external high temperature limit that asserts 'ALERT.

Variables
TaskHandle_t	vTaskMAX6642_Handle
	MAX6642 monitor Task Handle.

Detailed Description

MAX6642 I2C Temperature Sensor Interface implementation.

Author

Henrique Silva henri.nosp@m.que..nosp@m.silva.nosp@m.@lnl.nosp@m.s.br, LNLS

Function Documentation

MAX6642_init()

void MAX6642_init

(

void

)

Initializes MAX6642 sensor and creates vTaskMAX6642.

Returns

None

max6642_read_cfg()

uint8_t max6642_read_cfg

(

sensor_t *

sensor

)

Reads MAX6642 configuration byte.

Cfg byte:
[7] - MASK1 - Disables 'ALERT interrupts
[6] - STOP/RUN - Puts MAX6642 in standby mode
[5] - External Only - disables local temperature measurements so that only remote temperature is measured. The measurement rate becomes 8Hz.
[4] - Fault queue - (0):'ALERT is set by single fault; (1):Two consecutive faults are required to assert 'ALERT
[3:0] - Reserved

Parameters

sensor

Pointer to sensor info struct

Returns

Configuration byte

max6642_read_local()

Bool max6642_read_local	(	sensor_t *	sensor,
		uint8_t *	temp )

Reads MAX6642's local temperature value.

Parameters

sensor

Pointer to sensor struct

Returns

Temperature value

max6642_read_local_extd()

Bool max6642_read_local_extd	(	sensor_t *	sensor,
		uint8_t *	temp )

Reads MAX6642's local extended temperature value.

The extended value is the fractional part of the reading, with 0.25 oC steps. The value is the 2 MSBits returned.

Parameters

sensor

Pointer to sensor struct

Returns

Extended temperature value (2 MSB)

max6642_read_remote()

Bool max6642_read_remote	(	sensor_t *	sensor,
		uint8_t *	temp )

Reads MAX6642's remote temperature value.

Parameters

sensor

Pointer to sensor struct

Returns

Temperature value

max6642_read_remote_extd()

Bool max6642_read_remote_extd	(	sensor_t *	sensor,
		uint8_t *	temp )

Reads MAX6642's remote extended temperature value.

The extended value is the fractional part of the reading, with 0.25 oC steps. The value is the 2 MSBits returned.

Parameters

sensor

Pointer to sensor info struct

Returns

Extended temperature value (2 MSB)

max6642_read_status()

uint8_t max6642_read_status

(

sensor_t *

sensor

)

Reads MAX6642 status byte.

Status byte:
[7] - BUSY - Indicates the MAX6642 is busy converting data
[6] - LHIGH - Internal high temperature fault
[5] - Reserved
[4] - RHIGH - External high temperature fault
[3] - Reserved
[2] - OPEN - Diode open condition
[1:0] - Reserved

Parameters

sensor

Pointer to sensor info struct

Returns

Status byte

max6642_write_cfg()

void max6642_write_cfg	(	sensor_t *	sensor,
		uint8_t	cfg )

Writes MAX6642 configuration byte.

Cfg byte:
[7] - MASK1 - Disables 'ALERT interrupts
[6] - STOP/RUN - Puts MAX6642 in standby mode
[5] - External Only - disables local temperature measurements so that only remote temperature is measured. The measurement rate becomes 8Hz.
[4] - Fault queue - (0):'ALERT is set by single fault; (1):Two consecutive faults are required to assert 'ALERT
[3:0] - Reserved

Parameters

sensor	Pointer to sensor info struct
cfg	Configuration byte

Returns

None

max6642_write_local_limit()

void max6642_write_local_limit	(	sensor_t *	sensor,
		uint8_t	limit )

Sets internal high temperature limit that asserts 'ALERT.

Parameters

sensor	Pointer to sensor info struct
limit	High temperature limit value

max6642_write_remote_limit()

void max6642_write_remote_limit	(	sensor_t *	sensor,
		uint8_t	limit )

Sets external high temperature limit that asserts 'ALERT.

Parameters

sensor	Pointer to sensor info struct
limit	High temperature limit value

vTaskMAX6642()

void vTaskMAX6642

(

void *

Parameters

)

MAX6642 Monitor Task.

Parameters

Parameters

Pointer to parameter list passed to task upon initialization (not used here)

Variable Documentation

vTaskMAX6642_Handle

TaskHandle_t vTaskMAX6642_Handle

MAX6642 monitor Task Handle.