Guys,
I try try to create a custom DMA controller, and test it with OnChip memory. It has a single master for read and write (but I tried with separated masters for read and write - did not help).
The process is this:
1. Set read address, set burst size, assert read.
2. Read 16 bytes into a buffer, if finished then:
3. Set write address, set burst size, assert write - write out the buffer.
For one cycle it works, but if I try to repeat steps 123 123 123, at the second read I get wait-request at read assertion, and it hangs. Does not help if I re-assert the read.
If I remove the write assertion, so just repeat 12 12 12 12, it works well. Please study the attached pic. You see that reading only works well (top picture), but after one write the system hangs in wait request. Even if I assert a flush after writing.
Any idea what can I do?
