Dual FEC problems/CF5485

ChrisChelmecki — Thu, 27 Jul 2006 21:05:29 GMT

I am having trouble getting both FEC's to operate at the same time. Both work independently, but when I startup FEC0, then FEC1, I don't get
data received on FEC1. FEC0 is assigned DMA channel 2,3. FEC1 is assigned DMA channel 4(rx), channel 5(tx). The FEC1 transfer seems work properly, but when the server responds I never get an interrupt from the dma. FEC1 is also reporting rx overflow errors. All four dma channels used for the fec are low priority(1), but I have tried setting them higher. I am basically using the drivers from freescale. Any thoughts on what would cause problems when both FEC ports are operating? I am using an AXIOM eval board(for a Coldfire 5485).

Thanks,
Chris

Re: Dual FEC problems/CF5485

ChrisChelmecki — Wed, 02 Aug 2006 22:08:57 GMT

I just wanted to let people know what the problem was. We are using sram for buffers given to the DMA. When the second ethernet port was started, there wasn't enough sram left to allocate a buffer for the DMA. The DMA was getting a NULL pointer and not doing anything. So I decreased the number of buffers allocated for each port and it seems to be working properly.

Chris

ColdFire/68K Microcontrollers and ProcessorsのトピックRe: Dual FEC problems/CF5485

Dual FEC problems/CF5485

Re: Dual FEC problems/CF5485