RAM/PROM board for early S100 computers

Discuss construction, troubleshooting, and operation of the Altair 8800c computer
AltairClone
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RAM/PROM board for early S100 computers

Post by AltairClone »

For anyone who may have missed this in other forums, here’s a link to the FLEX64K RAM/PROM board that is designed to work around all the memory fragmentation that is common in early S-100 systems: https://deramp.com/flex64k.html

Mike
musovern
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Re: RAM/PROM board for early S100 computers

Post by musovern »

What a great board that you made.
I would of watched the video a few times now. :) It's help me get a Sub system B setup close to running.

I've got Mikes Flex64K board and a VDM-1 2021 board plus the 3S+P serial and have attach a ASCII keyboard plus serial port to the laptop.
I've now got Cuter to boot to the prompt and can dump memory etc, then tested a transfer of a program of to the Altair 8800c it's very slow transfer at 300 BAUD. Think I change this to 9600 over the weekend. Still learning about the CUTER Monitor, I also need to find a way to get ALS8 into EPROM next, I can not seem to find a BIN/HEX file for this.?

Still great fun.

Cheers
Vernon
setup-web.jpg
cuter_monitor_web.jpg
Attachments
serial_load_web.jpg
Last edited by musovern on August 9th, 2024, 4:22 am, edited 1 time in total.
Wayne Parham
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Re: RAM/PROM board for early S100 computers

Post by Wayne Parham »

That's awesome, guys!

Love that memory board!

Love that system!
AltairClone
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Re: RAM/PROM board for early S100 computers

Post by AltairClone »

Here’s a link where you can find cassette ALS8 (loads into RAM). I’ll find the patches I made to it to make an EPROM version and post that as well.

https://deramp.com/downloads/processor_ ... sol20.org/

Mike
musovern
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Re: RAM/PROM board for early S100 computers

Post by musovern »

That's great.
I might Disable ROM and ENABLE RAM at D000- FFFF and try the tape version. So easy to do this on the Flex64k board. I've now changed over my 3P +S for 9600 now. I see there is added a note that you added a 100ms delay for transfer at the sol20.org.

Just out of interest did you need to patch CUTER13.HEX from your download page it's the one I used in my system.?

Cheers
Vernon
Last edited by musovern on August 10th, 2024, 11:13 pm, edited 1 time in total.
AltairClone
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Re: RAM/PROM board for early S100 computers

Post by AltairClone »

Vernon,

No, I did not have to patch CUTER. Here’s a link to the ALS8 I put into EEPROM for the FLEX64K demo:

https://deramp.com/downloads/processor ... patch).HEX

This version takes keyboard input from the serial port on the 3P+S and outputs to the VDM board. Jump to E024 to start and to E060 to re-enter.

Mike
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Re: RAM/PROM board for early S100 computers

Post by musovern »

Thank you Mike,
That seems to have gone very easy thanks to your pre made hex file. Is it much work to make a .hex file for ASCII input for the 3P+S board and out to the VDM-1.?

I have only read though the ALS8 Assembler manual once so far, then typed in your example from your video. I got close. I'm guessing I have a space
or something not quite right as I had a error on line 0050, it's fun playing with these old assemblers.
ALS8.jpg

Cheers
Vernon
AltairClone
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Re: RAM/PROM board for early S100 computers

Post by AltairClone »

musovern wrote: August 13th, 2024, 5:42 pm Is it much work to make a .hex file for ASCII input for the 3P+S board and out to the VDM-1.?
Are you wanting to write a program that accepts keystrokes coming in through the 3P+S and displays them on the VDM-1?

Mike
musovern
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Re: RAM/PROM board for early S100 computers

Post by musovern »

Yes I have the 3P+S board connected to a ASCII keyboard and would like to use that to type on and display on the VDM-1, I have the serial connected to do transfers if needed.

Vernon
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Re: RAM/PROM board for early S100 computers

Post by AltairClone »

Try this using ALS-8 to assemble it. This should echo everything typed to the screen. Exit by pressing ESC (1Bh)

Code: Select all

LOOP CALL 0C01FH
 JZ LOOP
 CPI 1BH
 RZ
 MOV B,A
 CALL 0C019H
 JMP LOOP 
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