using PDC with SSC

This forum is for users of Microchip MPUs and who are interested in using Linux OS.

Moderator: nferre

Posts: 31
Joined: Thu Sep 16, 2004 3:10 pm

using PDC with SSC

Wed Feb 23, 2005 3:22 pm

I've been trying to set up the PDC to write characters to one of the SSC ports. Everything appears to be set up correctly and I'm getting the interrupt when the PDC is done transmitting, but I never see anything on the transmit line of the SSC. If I write directly to the transmit buffer I see the characters at the output.
Is there something that needs to be initialized to transfer the characters between the PDC and SSC?
David Peters
Alexander Saers
Posts: 9
Joined: Tue Dec 21, 2004 3:29 pm

Wed Mar 02, 2005 1:35 pm

Its because you are using virtual addresses that requires the mmu to resolve to the physical address.

Use the linux kernel function virt_to_bus to convert a virtual address to a physical. You must also use kmalloc with the __GFP_DMA flag to generate a physical continuous memory part

Return to “LINUX”

Who is online

Users browsing this forum: No registered users and 9 guests