This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

msp430f5438a I2C problems

Other Parts Discussed in Thread: PCA9554, MSP430F5438A, MSP430WARE

Hi,

On a ref board based on msp430f5438a , trying to communicate with I2C GPIO ex pander PCA9554_9554A and see things are not working as expected and flaky. To make development, easy i took the following codes from TI sources:

1. MSP430ware_1_90_00_30\examples\devices\5xx_6xx\MSP430F541xA_MSP430F543xA_Code_Examples\Cmsp430x54xA_uscib0_i2c_06.c - This transmits single byte to Slave device. This example works fine and no issues... Taking this further to send multiple bytes, i found another example as below

2: msp430x54xA_uscib0_i2c_12.c -> This failed to work for me. When i flash the code and run on the device, i see no pulse (checked with Oscilloscope).  

3. I did Google and found the below app note 

slaa382\USCI I2C Master Library\without DMA support -  When i try to compile for my device, it doesn't even compile... 

4. I also found other piece of code written around USCi library - usci_b_i2c\usci_b_i2c. - > Even this doesn't seem to work....same issue as no pulses.

I am so confused as to which is the working library or code. To put the blame on my HW design, tried all above pieces of code on my evaluation kit and see the same behavior.

When tried to debug the code, sometimes i see the clock seems to be busy always and it fails to start any transaction.

Can anyone please help me out on this? I am stuck from past 24hrs making no progress...

Thanks

Prashanth

**Attention** This is a public forum