Hi Everyone,
Looking for guidance on the Flex-Qspi operations.
I currently have a project that communicates with a FPGA, and I have been successful using the AHB to get and set registers on that FPGA. The issues occur when I am in a for-loop requesting data consecutively. I can see on the scope, the Flexspi control line is not always being toggled and the read returns with the same data that it had on the last read cycle (on failure). It seems like some times it gets 3 reads in a row successfully and then it would skip 1 and only issue a read on the following attempt.
I have been able to add "NOP" wait states to my for-loop to delay the next data request and it seems to remedy the situation. I just dont have an answer to why that is the case.
Here is a brief overview of my configuration for the data transfer:
Using DDR, Caching is Disabled, Prefetch is Disabled, Clearing is turned On after read.
Here is a look at what my transmission looked like:
Transmissions without NOP wait states:
Transmissions with NOP wait states added:
Can anyone offer any idea as to why the AHB is not triggering the data transmissions?
Thanks.
