dma questions

hello again!

Today i made some modifications to the SOPC project ( i added an external RAM) so i can run some more tests( ram-> onchip memory and onchip->onchip). Now the code and all the software components are on the ram.

The results are strange..to say the least. i observed the following situations:

onchip->onchip: works almost perfectly, but with a delay of one program run, for both chars and ints.(for ints works from the first run after i change the transfer type from onchip->onchip,and then gets this delay)

length=10
Transfer TX successful!
Transfer RX successful!
send 
5 6 7 8 9 10 11 12 13 14 
received 
1 2 3 4 5 6 7 8 9 10 
 int NOT OK 
 
 length=10
Transfer TX successful!
Transfer RX successful!
send 
5 6 7 8 9 10 11 12 13 14 
received 
5 6 7 8 9 10 11 12 13 14 
 int OK 
 
 length=10
Transfer TX successful!
Transfer RX successful!
send 
10 11 12 13 14 15 16 17 18 19 
received 
5 6 7 8 9 10 11 12 13 14 
 int NOT OK 
 
 length=10
Transfer TX successful!
Transfer RX successful!
send 
10 11 12 13 14 15 16 17 18 19 
received 
10 11 12 13 14 15 16 17 18 19 
 int OK 

ram->onchip : works perfectly for chars, but for ints is working only at the first run after i change the transfer type.

the thing is that earlyer this morning, the ram->onchip worked perfectly( for 12 ints) after i made this change in the code:

if ((rc = alt_dma_txchan_send (txchan,send,length*sizeof(int)*2,done_tx ,NULL)) < 0),

after that it didn't work anymore whith that *2. :confused:

Have a nice day! alex