tops20 assembly tutorials
dave at 661.org
Wed Mar 9 18:14:02 CST 2016
On Tue, 8 Mar 2016, Rich Alderson wrote:
> From: David Griffith
> Sent: Monday, March 07, 2016 11:53 PM
>> Specifically I'm trying to build and run this:
>> TITLE HACK
>> SEARCH MONSYM
>> HACK: SKIPA 4,[^D4]
>> HACK0: SOJL 4,TRAILL
>> SETZB 1,3
>> HACK1: TLNE 1,777777
>> JRST HACK0
>> MOVE 2,1
>> CIRC 2,-^D18
>> END HACK
>> When I do COMPILE, LOAD, and SAVE on it and run the executable, I get this:
>> ?Illegal instruction 247100,,777756 at HACK1+3
>> ?Undefined operation code
> As well you should. There is no CIRC in the standard PDP-10 instruction set.
> Opcode 247 is unassigned, so if someone defined CIRC locally (say, in an OPDEF,
> although I don't see one here), the result you report would be precisely what
> I would expect.
> Where did this code come from? From the presence of the LITES% JSYS I infer
> that it has something to do with Bob Armstrong's panel. Perhaps you should
> direct a query in his direction? SpareTimeGizmos.com, and all that.
I got it from Jan deRie when I asked about it on a Youtube video
showing the Panda Display in action. I'm trying to get it compiled
because I've made a new Panda Display board that connects to a USB port
instead of a parallel port. The new board works, but the lights don't
light up as expected, so I need something that puts a recognizable pattern
on the display.
I'm doing this with Bob Armstrong's blessing, but I haven't asked him
about this program yet. I'll post to the Spare Times Gizmos list now.
dave at 661.org
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