Al Ciplickas

UF32 as DMA host

Discussion created by Al Ciplickas on May 3, 2006
Latest reply on Mar 6, 2008 by Giang Tran Hoang
I'm wondering if anybody has enough experience with the UF32 to help me decide if using it might work as a DMA host. I was thinking of using the SM module to simulate the DREQ/DACK/DBWR functions. I only need to read from a device (a FIFO in this case) that has been taught to respond as a DMA output device. The transfer can happen in 512 byte blocks and I can ignore doing the 16 bytes of redundant data as well as not doing the ECC.

My questions are:
1-what lines (pins) are critical to have data movement?
2-what lines should be set constant values (/SBSY=1, /SCD=0)?
3-do I note SCLE=0 and SALE=0 during the /SRE time?
4-is /SRE the only line that I need to look at for data requests?

Has anyone tried this yet? It would be good to be able to use a UF32 module to do this transfer into a QUE buffer to avoid bit-banging, which uses up CPU time. I want to be able to move this data to a host via the USB module.

Thanks, -Al-