tops20 assembly tutorials

[David Griffith]

On Mon, 7 Mar 2016, Rich Alderson wrote:

> From: David Griffith
> Sent: Saturday, March 05, 2016 9:36 PM
>
>> Would someone please point me towards a tutorial of some sort on running
>> the assembler on TOPS20 as presented in Mark Crispin's Panda distribution?

[snip]

> COMPILE does only that.  LOAD will compile if necessary and link the result
> into an executable image in memory (which can be saved as an executable
> program file with the SAVE command).  EXECUTE and DEBUG will compile if
> needed, link, and respectively either simply start running or invoke DDT
> and leave you ready to execute, examine memory, etc.
>
> Do you need a pointer to the user commands manual?
>
> http://www.bitsavers.org/pdf/dec/pdp10/TOPS20/V7/USERS.MEM.txt

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
         SKIPN 4
          SKIPA 1,3
           IOR 1,3
         LITES%
          HALT
         HRRZ 2,1
         MOVEI 1,30
         DISMS%
         MOVE 1,2
         AOJA 1,HACK1

TRAILL: SETZ 1,
TRALL0: LITES%
          HALT
         MOVE 2,1
         MOVEI 1,30
         DISMS%
         JUMPL 2,TRAILR
         LSHC 1,^D37
         AOJA 1,TRALL0

TRAILR: MOVSI 1,400000
TRALR0: LITES%
          HALT
         MOVE 2,1
         MOVEI 1,30
         DISMS%
         MOVE 1,2
         TRNE 1,1
          JRST HACK
         ASH 1,-1
         JRST TRALR0

         END HACK

When I do COMPILE, LOAD, and SAVE on it and run the executable, I get 
this:

$hack
?Illegal instruction 247100,,777756 at HACK1+3
?Undefined operation code

-- 
David Griffith
dave at 661.org

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