TD Systems TDL-11 QBUS (SCSI?) card

Noel Chiappa jnc at mercury.lcs.mit.edu
Mon May 4 07:38:31 CDT 2015


    > From: Seth Morabito

    > 1. Halt the CPU and enter ODT

I'm too lazy to check to confirm this, but I strongly suspect DMA requests
don't get serviced while the machine is halted. If so, you could use the
following code fragment to avoid that:

	0400	12737	MOV	#400, @#174400
		400
		174400
		777	BR	.

Start at 0400, let it run for a couple of seconds, then halt the machine
and look at 01000 and up.

	Noel


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