I2C Bus busy Issue

Mohanmurali M

Other Parts Discussed in Thread: MSP430F67791A

We are using MSP430f67791A Controller for our Project. In our Project if we enable I2C alone we can able to Transfer data without any issue. Along with I2C if we enable RTC,Timer and ADC, I2C transaction happening for sometimes and after that I2C bus becomes busy.

We observed that one of the variable is not getting set in the I2C Interrupt routine. During further Analysis we observed that handling of ADC (We disabled RTC and Timer) is corrupting the variable used in the I2C interrupt routine and because of that I2C transactions are not happening properly..

Also during search in the websites, in some websites it is mentioned that handling of ADC in MSP430 will corrupt the memory section. Is it true?.

Please provide suitable suggestions to overcome for this issue.

Thanks & Regards,

Mohan Murali

over 9 years ago

0 Clemens Ladisch over 9 years ago

Guru 320660 points

Check erratum USCI37. If you using DMA, also look at errata DMA7 and DMA9.

0 Mohanmurali M over 9 years ago in reply to Clemens Ladisch

Prodigy 220 points

Hi Clemens Ladisch ,

Thanks for your response. We have gone through the errata USC137 and understand the situation at which the I2C Bus hang issue will happen. But we are not able to completely understand the solution provided in the errata to overcome the hang issue. Please provide more information on the solution.

It will be useful if you provide some sample code for the solution.

Thanks,

Mohan murali

0 Clemens Ladisch over 9 years ago in reply to Mohanmurali M

Guru 320660 points

To use the first USCI37 workaround, read the RXBUF register twice.

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I2C Bus busy Issue