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+--- Thread: DGOS 1.4+ (/thread-310.html)
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RE: DGOS 1.4+ - nauseous - 08-02-2022
Just quickly, the PROM I have contains string "DGOS 1.4 c1980"
RE: DGOS 1.4+ - ChickenMan - 08-02-2022
The have also the DGOS 1.4 source code also if that helps, but compiles to a 2kb file.
0001 : ********** D G 0 S **********
0002 : WRITTEN BY DAVID GRIFFITHS
0003 : COPYRIGHT © 1980
0004 ;
0005 ; THIS SOFTWARE MAY NOT BE DUPLICATED WITHOUT
0006 ; THE PRIOR WRITTEN CONSENT OF THE COPYRIGHT
0007 ; HOLDER.
0008 ;
0009 ; DG OPERATING SYSTEM IS A MACHINE CODE
0010 : MONITOR INTENDED FOR USE WITH THE DG 680
0011 : CPU BOARD.
0012
0013 ; DISASSEMBLED BY DAVE WILLIAMS USING DISILOG.
0014 : EDIT WITH WORDMASTER. REASSEMBLED WITH
0015 : Z80 ASSEMBLER UNDER CP/M. JAN 1981.
0016 ;
0017 ;
0018 ; DGOS VER 1 4
We also have the ETI680 rom (a 2kb file) that contains the code "DGOS 1.4 c1980"
RE: DGOS 1.4+ - nauseous - 08-02-2022
OK, I assume that is exactly what I am looking at here (ETI680 ROM).
The other two PROMS where located at the bottom end of address space, the "DGOS 1.4 c1980" PROM was located at 6000h.
So question here; I can't find a photo of an ETI680 card, but did it have the ROM onboard?
RE: DGOS 1.4+ - ChickenMan - 08-02-2022
Yes the rom was onboard, here is a pic of an eti680
RE: DGOS 1.4+ - someone - 09-02-2022
It's great to see another DG680 CPU intact!
Yours has quite a few odd mods. Can you post a more detailed close up photo of it?
Someone'd stay with DGOS 1.4 as its the best for getting things going.
It's designed to work with just a DG680 CPU and DG640 VDU installed so start with that configuration first.
If using the DG0S 1.4 - ensure that the POJ DIP switches are set correctly to %D000.
It appears you're missing an IC38 (74LS139) to the right near the Z80 CTC - make sure that this installed.
It is also advisable to wind down the CPU oscillator to 2MHz at first.
What IC is inserted at position 26? It should be a 74S200 or equivalent - these have always been rare and expensive.
(Note: DGOS 1.4 will work just fine without a 74S200 installed.)
If things are really pear, then see if you can get some 2716 (single voltage) EPROMs and write your own diagnostic boot ROMs.
e.g. Write a single byte in a ROM with %76 (Halt Instruction) to turn on the HALT LED.
Good luck!
RE: DGOS 1.4+ - ChickenMan - 09-02-2022
Sorry, but this is not my DG680 board but a pic I acquired recently. I'm hoping the ACMS will obtain the unit and I will then be able to get a better picture.