Si7021 Functions

Detailed Description

Si7021 driver and support functions.

Functions
uint32_t	SI7021_cmdRead (uint8_t *cmd, size_t cmdLen, uint8_t *result, size_t resultLen)
	Sends a command and reads the result byte(s) over the I2C bus. More...
uint32_t	SI7021_cmdWrite (uint8_t *cmd, size_t cmdLen, uint8_t *data, size_t dataLen)
	Sends a command and data to the chip over the I2C bus. More...
void	SI7021_deInit (void)
	De-initializes the Si7021 chip. Disables the sensor power domain, this also disables other sensors. More...
uint32_t	SI7021_getFwRev (uint8_t *fwRev)
	Reads the firmware revision of the Si7021 chip. More...
uint32_t	SI7021_init (void)
	Initializes the Si7021 chip. More...
uint32_t	SI7021_measure (uint32_t *rhData, int32_t *tData)
	Performs relative humidity and temperature measurements. More...

Function Documentation

uint32_t SI7021_cmdRead	(	uint8_t *	cmd,
		size_t	cmdLen,
		uint8_t *	result,
		size_t	resultLen
	)

Sends a command and reads the result byte(s) over the I2C bus.

Parameters

[in]	cmd	The command to be sent
[in]	cmdLen	The length of the command in bytes
[out]	result	The received bytes sent by the chip
[in]	resultLen	The number of the bytes to read from the chip

Returns

Returns zero on OK, non-zero otherwise

Definition at line 188 of file si7021.c.

References I2C_TransferSeq_TypeDef::addr, I2C_TransferSeq_TypeDef::buf, I2C_TransferSeq_TypeDef::data, I2C_TransferSeq_TypeDef::flags, I2C_FLAG_READ, I2C_FLAG_WRITE_READ, I2CSPM_Transfer(), i2cTransferDone, i2cTransferNack, I2C_TransferSeq_TypeDef::len, SI7021_ERROR_I2C_TRANSFER_FAILED, SI7021_ERROR_I2C_TRANSFER_NACK, SI7021_I2C_BUS_ADDRESS, SI7021_I2C_DEVICE, and SI7021_OK.

Referenced by SI7021_getFwRev(), SI7021_init(), and SI7021_measure().

uint32_t SI7021_cmdWrite	(	uint8_t *	cmd,
		size_t	cmdLen,
		uint8_t *	data,
		size_t	dataLen
	)

Sends a command and data to the chip over the I2C bus.

Parameters

[in]	cmd	The command to be sent
[in]	cmdLen	The length of the command in bytes
[out]	data	The data byte(s) to be sent to the chip
[in]	dataLen	The number of the bytes to be sent to the chip

Returns

Returns zero on OK, non-zero otherwise

Definition at line 247 of file si7021.c.

References I2C_TransferSeq_TypeDef::addr, I2C_TransferSeq_TypeDef::buf, I2C_TransferSeq_TypeDef::data, I2C_TransferSeq_TypeDef::flags, I2C_FLAG_WRITE, I2C_FLAG_WRITE_WRITE, I2CSPM_Transfer(), i2cTransferDone, i2cTransferNack, I2C_TransferSeq_TypeDef::len, SI7021_ERROR_I2C_TRANSFER_FAILED, SI7021_ERROR_I2C_TRANSFER_NACK, SI7021_I2C_BUS_ADDRESS, SI7021_I2C_DEVICE, and SI7021_OK.

Referenced by measureSupplyIR(), and SI7021_measure().

void SI7021_deInit

(

void

)

De-initializes the Si7021 chip. Disables the sensor power domain, this also disables other sensors.

Returns

None

Definition at line 74 of file si7021.c.

Referenced by UTIL_supplyProbe().

uint32_t SI7021_getFwRev

(

uint8_t *

fwRev

)

Reads the firmware revision of the Si7021 chip.

Parameters

[out]

fwRev

The firmware revision of the chip

Returns

Returns zero on OK, non-zero otherwise

Definition at line 157 of file si7021.c.

References SI7021_CMD_READ_FW_REV, and SI7021_cmdRead().

uint32_t SI7021_init

(

void

)

Initializes the Si7021 chip.

Returns

Returns zero on OK, non-zero otherwise

Definition at line 41 of file si7021.c.

References BOARD_envSensEnable(), SI7021_CMD_READ_ID_BYTE2, SI7021_cmdRead(), SI7021_DEVICE_ID, SI7021_ERROR_INVALID_DEVICE_ID, SI7021_OK, and UTIL_delay().

Referenced by UTIL_supplyProbe().

uint32_t SI7021_measure	(	uint32_t *	rhData,
		int32_t *	tData
	)

Performs relative humidity and temperature measurements.

Parameters

[out]	rhData	The measured relative humidity value in milli-percent units
[out]	tData	The measured temperature value in milli-degree Celsius

Returns

Returns zero on OK, non-zero otherwise

Definition at line 94 of file si7021.c.

References SI7021_CMD_MEASURE_RH_NO_HOLD, SI7021_CMD_READ_TEMP, SI7021_cmdRead(), SI7021_cmdWrite(), SI7021_ERROR_I2C_TRANSFER_NACK, SI7021_ERROR_TIMEOUT, SI7021_OK, and UTIL_delay().