xenix 2.3.2 trap D on 486

[John Watson]

Help, I am getting a TRAP 000D when ever two DMA devices like HD & FD
are used at the same time, like swap while reading fd, or copy FD to a
file on HD.  I have tried setting DMAEXCEL to both 1 & 0, it seems
to make no difference.  CACHE Enable/Disable also no effect.

The processor is a 486 (no brand/Tiwan) using an 82C206 for DMA and
82C481 & 82C482 for Cache control.

Any help appreciated, quick please.    John Watson ...!rutgers!carssdf!usenet