#Mask for DMA to chip ram
2 messages in this thread
Can someone tell me what mask to use to restrict DMA to chip ram only? My
Derringer equipped A2000 locks up occasionally when transfering files with the
networking software Amiga Link. I tried using mask 0x00fffffe, DMAing to the
24bit space and not the non-DMA 32bit ram on the Derringer but that didn't
work. Another fellow Amigaian using a Derringer and Amiga Link also has the
same problem so it may be a bug with the Derringer. Come to think of it, can I
stop all DMA from the one drive (out of three) I share out on the Derringer
A2000 (I'm using a GVP series II controller)? Thanks in advance.
JMC
JC >>what mask to use to restrict DMA to chip ram only?<<
I was under the impression that a MASK of 0xfffffe, would restrict DMA to
the first 2-megs of address space. You might try 0xffffe.
Also, you have to set the MASK for EACH partition.
If you have multiple partitions, but only limit the DMA MASK on the first
partition, the other partitions could still try to access a larger DMA
area, and be causingthe lockups.
Ron. – ("I'm not stupid, I'm not expendable, and I'm not going!"
– quote made by any low level RPG player.)