SK-AM64: Issue with the i2c

shruti gupta

Part Number: SK-AM64

Hi ,

I am trying to integrate BOOSTXL-ADS7142-Q1 (ADC) with the skam64 for my use case , for the communication between them I am using the i2c module from the processor , i2c0 instance is being used for the clk and data line , to verify the slave device , I did use the API I2C_probe(i2cHandle, 0X18) , but the adc is not acknowledging the processor , could anyone please help me with this issue

Regards,

Shruti Gupta

over 1 year ago

0 Bin Liu over 1 year ago

TI__Guru*** 140946 points

Hi Shruti,

What OS do you run on SK-AM64, Linux or FreeRTOS?

0 shruti gupta over 1 year ago in reply to Bin Liu

TI__Expert 4860 points

I'm using FreeRTOS

0 Bin Liu over 1 year ago in reply to shruti gupta

TI__Guru*** 140946 points

I am routing your query to the FreeRTOS team for comments.

0 Vaibhav Kumar over 1 year ago in reply to shruti gupta

TI__Mastermind 22643 points

Hi Shruti,

Thanks for the setup.

Just to clear once again: You are trying to read (0x20) which is an internal register to ADC.

I will debug through the I2C code you sent me and go through it.

Expect a response by EOD.

Regards,

Vaibhav

0 shruti gupta over 1 year ago in reply to Vaibhav Kumar

TI__Expert 4860 points

yes , so ideally you should get 0x3 at the address 0x20 , thanks for the response

0 Vaibhav Kumar over 1 year ago in reply to shruti gupta

TI__Mastermind 22643 points

Hi Shruti,

A quick update. I could not get the value at 0x20 to be 0x3, instead it was showing 0x24.

I will dig deeper and find out what could be the root cause.

Regards,

Vaibhav

0 shruti gupta over 1 year ago in reply to Vaibhav Kumar

TI__Expert 4860 points

Okay , thanks ....let me know if you get the correct values

0 shruti gupta over 1 year ago in reply to shruti gupta

TI__Expert 4860 points

Hi Vaibhav ,

The issue has been resolved , because of the multiple pullup resistors with i2c pins , there were some threshold level issue , since we have 2 pullup resistors in skam64 i2c pins , and here in ads7142 we have 4 pull up resistors with i2c pins , removing the pullup resistors from ads7142 will work , sharing the correct i2c captures here , initially the acknowledgement was not coming out properly , by removing the pullup resistors , we are getting the correct read and write captures

0 Vaibhav Kumar over 1 year ago in reply to shruti gupta

TI__Mastermind 22643 points

Hi Shruti,

Thanks for updating. I am closing the thread as your problem as has been resolved.

For anyone going through this E2E thread: Desoldering the pull up resistors namely R17, R18, R24 and R25 on ADS7142 board worked for Shruti.

Regards,

Vaibhav

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SK-AM64: Issue with the i2c