Tom's computer pages

March 10, 2022

Silicon Graphics Multibus "IP2" board -- PALASM under FreeDOS

I have an entire computer dedicated to running FreeDOS. I find this necessary because I have a MOD_EMUP prom burner that has an ISA interface card as well as DOS software. This all works out in a satisfactory manner, if you can even apply the word "satisfactory" to using DOS in this day and age.

This machine also has an old copy of PALASM, and I have found that I am able to use that copy to disassemble JEDEC files that I have read from PAL devices using the MOD_EMUP.

The version of PALASM I have on this machine is an older version labeled "PALASM Beta release", but it has always worked fine for me, in fact I can do things with it that I have so far been unable to do with PALASM4, which is widely available online.

I'll also note that the problems I had with it initially on my FreeDOS machine were all related to getting it installed properly, which was all about the PALASM variable and PATH in the autoexec.bat file.

Here is the "recipe".

Move the .JED files to the /palasm directory
type PALASM to launch PALASM
use the right arrow key to select "RUN" in the top menu
select "Others ..." from the run menu (arrow down and hit return)
select "disassemble JEDEC" from the next menu that appears
fill in the form that appears (see below)
hit F10 to do the disassembly

Their way of menu navigation takes some getting used to. There is often useful help and suggestions at the bottom of the screen. Note in particular that you use F10 to indicate that a form has been completely filled out and should be acted on. To select the device type from a list, use F2.

Page-up and Page-down can be handy within big menus (like the device list). Also it works just fine to enter lowercase for filenames.

My jedec files have names like "sgi72.jed" and I want the disassembly output to be placed in "sgi72.pl2". I must type "n" (for "no") to the "Palasm jedec file?" question, and this triggers the option to select the device type from a list. Palasm does not accept the JED files generated by the MOD-EMUP if I answer yes.

Feedback? Questions? Drop me a line!

Tom's Computer Info / tom@mmto.org