You should be able to use DMA_RDY_CT i.e. this signal says whether the DMA is ready to receive or send data. If a transfer is tried when it is not true i.e. the DMA is not ready you can use that to find out the overflow, underflow condition.
I cannot find the symbol DMA_RDY_CT. I searched all the .c and .h files within the directory where I installed the Cypress SDK and didn't find it.
The condition of the FIFO FULL and my attempting to write into the buffer may only occur very briefly on the interface. Will this flag latch that occurrance? IE: will it remain TRUE after the physical occurrence has gone away?
Can I use this occurrance to generate an interrupt?
This answer was verified unintentionally. I have opened a tech support case to elevate this issue.