EQADC Result FIFO overflow is disturbing storage of results at the right software locations

[nandus]

Hi,

I am converting 32 commands of analog input through EQADC of MPC5566 controller. I am using 5th command FIFO and using EDMA channel 11 to transfer commands from user software command buffer to CFIFO 5 and configured sampling time as 8 ADC clock cycles. The clock used here is 144Mhz.

 EDMA channel 12 is used to tranfer result from RFIFO 5 to software managed result queue.

I have observed that there is a mismatch in the storage of results at the correct location of software queue that has been set by user and this is occurring when result fifo overflow flag is set. I configured result overflow fifo overflow interrupt and adjusted or realigned the result queue. But I want to know what is the root cause for this. Can anybody help me to find the root cause for buffer mismatch?

Thanks in Advance,

Raghu.

[Mahantesh]

Hi Raghu,

I am also facing the similar problem.

I am using MPC5674, using CFIFO1 and RFIFO1.

Because of RFIFO1 overflow, the software result array is getting filled with wrong values.

Could you please tell me how did you realign result queue..??

[nandus · Accepted solution]

Hi Mahantesh,

The issue was that the commands were getting corrupted due to memory override from another feature(I guess EDMA) that I was using in my application. So I have realigned the memory allocations and it worked.

Thanks,

Raghu.