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Ragooman
June 10th, 2010, 07:20 AM
I found this at Breezeshooter's Hamfest last wknd in the Pittsburgh area.
This is a PAL programmer made by Structured Design, SD 30/24 -- pic avail at link below
It even includes a Stringy Floppy cassette player, plus a spare cassette--I hope I can find these too.
This is supposed to be a standalone programmer with just a serial port for console input and display.

Would someone know where I can find a manual for this PAL Programmer ?
I tried the usual websites, starting with bitsavers, but no luck so far.
http://tinyurl.com/2fxwb26

thanks
=Dan

dave_m
June 10th, 2010, 11:59 AM
Wow, this brings back memories. Back in 1980 I used a SD20 to program the first generation of bipolar PALs from Monolithic Memories (MMI). Your unit seems to be an improved version that can program the later 24 pin devices also. Hook up the serial port to a dumb terminal or a PC running a term program. Try 1200 baud if it is not selectable on the SD20. I think when the SD20 powers up, it sends a menu to the terminal. The commands were very basic. There was an edit mode that allowed you to type in a PALASM Design Specification. One could save the source file to the stringy tape unit. Then there were assemble, plot (shows fuses), verify and program commands. I’m not sure if it could save a JEDEC output file.

These SD units are not very useful anymore as they only program the old bipolar fuse type PALs which are one time programmable. The newer erasable CMOS types like the22V10, GALs, etc. use different programming algorithms.
-Dave

Ragooman
June 10th, 2010, 12:36 PM
Yes, this also brings memories for me too. I used a different model, can't remember the model#, but it had a builtin screen instead of using a terminal - and no stringy floppy. We had to use these worksheets from the manual to build the design. And you had better save them too if you didn't want to forget what you programmed :)

I still have to check the inside and clean it out before attempting to run this. You can still find the original PAL's on eBay, I was trying to find some other suppliers in the meantime. I don't mind using the older PAL's.

=Dan

dave_m
June 10th, 2010, 01:11 PM
We had to use these worksheets from the manual to build the design.
OK, that sounds like the older way of using fuse maps and telling the system what fuses to keep. PALASM made life easier as you would write boolean equations and function tables. It was the forerunner of ABEL and VHDL type design tools. PALASM was simple as you would only need to write the equations as 'sum of products'. PALASM firmware is built into the SD20/24.


You can still find the original PAL's on eBay, I was trying to find some other suppliers in the meantime. I don't mind using the older PAL's.
To be safe, make sure you buy MMI or National Semi parts only. TI and other vendors of PALS used different algorithms which the SD20 may not fuse properly.

You have an historic piece of hardware as Structured Design was founded by John Birkner, one of the inventors of the PAL at MMI. I think he also wrote the first PAL Assembler code (PALASM).

I have a MMI PAL Handbook around if you need information on PALASM but you may find a lot on the web.
Best of luck on this project.
-Dave

Ragooman
June 11th, 2010, 10:35 AM
I remember PALASM too. I was relived when this came out. I still have a copy of this, along with some other tools, such as ABEL and CUPL, I have to see if I can run these. If PALASM firmware is builtin to this programmer, that would be great and make like easier. I might want to ask you some questions from that manual as I get this cleaned out and running

I just found this webpage about a reunion for MMI employees
http://www.vaughns-1-pagers.com/history/mmi-employees.htm

=Dan