Data Sheet

ams Datasheet Page 19
[v1-01] 2017-Mar-17 Document Feedback
AS7262 − Detailed Description
I²C Virtual Register Byte Write
Pseudocode
Poll I²C slave STATUS register;
If TX_VALID bit is 0, a write can be performed on the interface;
Send a virtual register address and set the MSB of the register address to 1 to indicate the pending write;
Poll I²C slave STATUS register;
If TX_VALID bit is 0, the virtual register address for the write has been received and the data may now be written;
Write the data.
Sample Code:
#define I2C_AS72XX_SLAVE_STATUS_REG 0x00
#define I2C_AS72XX_SLAVE_WRITE_REG 0x01
#define I2C_AS72XX_SLAVE_READ_REG 0x02
#define I2C_AS72XX_SLAVE_TX_VALID 0x02
#define I2C_AS72XX_SLAVE_RX_VALID 0x01
void i2cm_AS72xx_write(uint8_t virtualReg, uint8_t d)
{
volatile uint8_t status;
while (1)
{
// Read slave I²C status to see if the write buffer is ready.
status = i2cm_read(I2C_AS72XX_SLAVE_STATUS_REG);
if ((status & I2C_AS72XX_SLAVE_TX_VALID) == 0)
// No inbound TX pending at slave. Okay to write now.
break;
}
// Send the virtual register address (setting bit 7 to indicate a pending write).
i2cm_write(I2C_AS72XX_SLAVE_WRITE_REG, (virtualReg | 0x80));
while (1)
{
// Read the slave I²C status to see if the write buffer is ready.
status = i2cm_read(I2C_AS72XX_SLAVE_STATUS_REG);
if ((status & I2C_AS72XX_SLAVE_TX_VALID) == 0)
// No inbound TX pending at slave. Okay to write data now.
break;
}
// Send the data to complete the operation.
i2cm_write(I2C_AS72XX_SLAVE_WRITE_REG, d);
}