Short PDP-8 Memory Test...

[Mike Katz]

Another PDP-8E?????  You are very lucky :)

On 4/6/2022 1:06 PM, Lyle Bickley via cctalk wrote:
> I recently acquired another PDP-8/E and wanted to test basic CPU functions and
> memory before I added peripherals. There are some available short "memory
> tests" online, but most don't have have the flexibility to test multiple data
> patterns by design.
>
> The test below does a classic checkerboard type test - and permits easy
> modification of the data pattern used in testing.
> ---
> # Easy to enter, short memory test for PDP-8 systems
> # prior to adding peripheral equipment.
> # by Lyle Bickley
> #
> # Location 21 initially contains a zero. Therefore the
> # memory test is 0000 and 7777 in alternate locations.
> # Changing this location to 7070 will test 7070 and
> # 0707 in alternate locations. Changing it to 5252 will
> # test 5252 and 2525, etc.
>
> 0000 7300 CLA CLL
> 0001 1022 TAD 22
> 0002 3023 DCA 23
> 0003 7300 CLA CLL
> 0004 1021 TAD 21
> 0005 7040 CMA
> 0006 3021 DCA 21
> 0007 1021 TAD 21
> 0010 3423 DCA I 23
> 0011 1021 TAD 21
> 0012 7041 CMA IAC
> 0013 1423 TAD I 23
> 0014 7440 SZA
> 0015 7402 HLT (ERROR - AC SHOWS FAIL)
> 0016 2023 ISZ 23
> 0017 5003 JMP 3 (INC LOCATION AND LOOP)
> 0020 5000 JMP 0 (START OVER)
> 0021 0000 (0=ALT 7777 AND 0000)
> 0022 0025 (LOCATION TO START TEST - MAKE ODD)
> 0023 0000 (LOCATION BEING TESTED)
> ---
>
> Cheers,
> Lyle