TM4C123BH6ZRB: Transmitting Multiple I2C Bytes

Akash Patel

Part Number: TM4C123BH6ZRB

Hi team,

We are working with the TM4C123BH6ZRB in our design using the I2C peripheral. Is it possible to transmit multiple bytes of data over I2C on an interrupt on this device as a slave?

The TM4C129x devices have the FIFO which can trigger when full or at a certain level in order to transmit multiple bytes of data from the FIFO but this device does not have a FIFO.

Regards,

Akash Patel

over 8 years ago

0 Bob Crosby over 8 years ago

TI__Guru 72500 points

Yes, but the master must initiate the transfer.

0 Akash Patel over 8 years ago in reply to Bob Crosby

TI__Expert 6245 points

Hi Bob,

Thanks for the confirmation. What are the Driver Lib commands to do this? Is there something we have to set in particular to get this to work?

Regards,
Akash

0 Bob Crosby over 8 years ago in reply to Akash Patel

TI__Guru 72500 points

During initialization you need to call I2CSlaveIntEnable(). In the interrupt routine you check for the transmit request bit (TREQ). You can use the I2CSlaveStatus function "anded" with I2C_SLAVE_ACT_TREQ. Then use I2CSlaveDataPut() to transmit the data. There are other possibilities and without writing the code I cannot be more specific. You can review all of the I2C driver functions in chapter 16 of the Driver Library User's Guide.

0 Akash Patel over 8 years ago in reply to Bob Crosby

TI__Expert 6245 points

Hi Bob,

From my understanding and the from the user's guide it says the I2CSlaveDataPut "Transmits a byte from the I2C Slave." This will only send one byte, is there a way to transmit multiple bytes in one command?

Once the master requests that the slave transmits data and we enter our ISR, do we need to just call the I2CSlaveDataPut for however many bytes we wish to transmit?

Regards,
Akash Patel

0 Bob Crosby over 8 years ago in reply to Akash Patel

TI__Guru 72500 points

Your understanding is correct. On this device you must call I2CSlaveDataPut for each byte requested.

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TM4C123BH6ZRB: Transmitting Multiple I2C Bytes