rolffson's 1401 datacenter 3D simulation


- address calculation sheet
- simh ex dump formatter
- tiny load card assembler

2021-10-11 - in the future, I will use LibreOffice instead of OpenOffice, e.g. for the spreadsheet tools below.
                        Files may still work with OO, but I won't test it.

memory address calculator         ⌂ home   ↑ top

quick address translation between decimal and 3-char representation
simply type an address in column B/F, and see result in column C/G

download the "H1401 address calculator vx.ods" (LibreOffice) from the download folder: download


simh ex dump formatter         ⌂ home   ↑ top

while using the 1401 SIMH simulator to compare results to the VDC to help find bugs, I missed the 'dump' command,
which doesn't seem to be implemented in the 1401 simh (at least in the version I used).
Unfortunately the ROPE system also doesn't work on my PC (don't know why, maybe java issues).
Instead of implementing it myself into the simh source, I decided to use the simh 'ex 0-15999' command, combined with a
preceding 'set console log= <file>' command to get a list of all memory locations.

This spreadsheet helps creating a nicely formatted table with characters and word marks from this export.
Simply copy and paste the text part with the memory export from the log result into A1.

download the "SIMH 1401 ex dump beautifier vx.jpg" (LibreOffice) from the download folder: download


tiny load card assembler         ⌂ home   ↑ top

last update 2021-07-22 (v4)


This spreadsheet helps creating a stack of cards which can be read into the 1401 memory using the 1402 LOAD function.
It also offers a lightweight assembler which calculates addresses and labels.

special feature: you may use "&<label>" format to address the right/upper address of a data field, just as required by e.g. the M command.

currently only working with openOffice; needs some work to run with Excel.

download the "H1401 program sheet v? - program template.ods" (LibreOffice) from the download folder: download   

you may enter the program on the "program sheet" and add data on the "data sheet".
the resulting card stack can then be copied from the "cards" sheet.

see youTube video for a demo:

on the "program sheet" and "data sheet", you may insert or delete rows in the program/data area w/o disturbing the processing
(e.g. by marking lines with shift-space and then pressing ctrl-<plus> or ctrl-<minus>)

pls. follow the rules and hints written in the file.
it's a very simple 'assembler' based only on spreadsheet functions, so don't expect too much.

CAUTION: up to v5, the "jump to program start" on the last card always pointed to 501, independent
of the actual program start. Correct it manually, or download the latest version.

CAUTION: the current version only allows addresses up to 999 and also does no error checking on label names.
If a label is misspelled, the related address will be wrong or missing on the card. The resulting card stack will behave strangely.
Always check the result on the 'cards' sheet for suspicious expressions.

tiny assembler arr ta2

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