MSPM0G3507: How to control sending out the restart in I2C communication

Crane Shao

Part Number: MSPM0G3507

Tool/software:

Hi,

I am working on I2C communication to an I2C sensor and trying to control sending out the restart.

But from the below functions provided by driverlib, there is no control on this:

DL_I2C_startControllerTransfer()

DL_I2C_startControllerTransferAdvanced()

I do find this from dl_i2c.h where restart is mentioned:

But I couldn't find WBLEN anywhere from both the driver and the TRM.

Can anyone help with this?

Thanks!

Crane

0 Bruce McKenney 5 months ago

Guru 99405 points

If this is a simple write-then-read transaction ("register" model) the simplest way is to use the RD_ON_TXEMPTY feature. The idea is:

1) Set the I2C_MCTR_RD_ON_TXEMPTY_ENABLE bit in MCTR.

2) Put the Write part (register number) into the Tx FIFO

3) Start the Read part with DL_I2C_startControllerTransfer() (don't count the Tx FIFO contents in the length).

The I2C unit will do a Write transfer with the Tx FIFO contents, then issue a Restart for the Read transfer.

Driverlib provides a function DL_I2C_enableControllerReadOnTXEmpty() to set the bit, but see also:

+1 Crane Shao 5 months ago in reply to Bruce McKenney

Ok great. Thanks Bruce!

Regards,

Crane

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