DGOS 1.4+

[gentle1]

Hi,

I thought this may be of interest to someone as there seems to be no information around this monitor version. 
I am also keen to hear if anyone else is using this monitor.
I have been running the DGOS 1.4+monitor in my DG680 since the 80's however I haven't seen any mention of it on the net or this forum. 
The 1.4+ monitor has functions such as single stepping, break points, watch points, port I/O and more. 
I have/had the source for it on an 8" floppy but have killed all of my 8" floppy drives with a bad supply so can't retrieve the source :-( . 
I had customised my version to cater for a video card that I built. However I have just found that there is an implementation of the dg680 on Mame and have modified the dg680 module to support the 3 ROM 6k monitor and added an image of the 32 byte prom.  As such I have patched the ROMs to run with the ETI640 video. 

If anyone is interested in upgrading from the original DGOS 1.4 monitor I can supply the bin files for the 3 roms. 
The monitor occupies memory addresses C000H through to D7FFH.

Cheers Bruce

[ChickenMan]

As your probably seen, we only have the original DGOS 1.4 as a binary and asm listing in the repository and yes, there has been very little talk about even that. If you can attach your modified rom to post or pm me a link to them, we can certainly make them available to everyone. Thanks.

[someone]

G'day Bruce,
Someone is still a very active user of their DGZ80 S100 and related systems and is very interested with the ROMs you've mentioned.
Someone still has an IBM 8" floppy drive - although it hasn't been powered up for over a decade.
There's meant to be two additional DGOS versions later than 1.4. One to support the DG750 I/O card and the other for the MW6545 video card but someone has never seen them. It'd be great to discover these times.

Cheers!

[gentle1]

Hi Someone,

I have had a look at the MW6545 and it is using the same crt controller chip that I used in my video card. As there wasn't enough space in any of the 3 monitor roms when I compiled the monitor I put a call to another block of code in another rom to initialise the registers of the controller. All other initialisation for the video is identical as it is memory based video. The block of code to initialise the registers is about 20 bytes and is easy to setup.

I Haven't come across the DG750 I/O card if you have any info I would be interested in having a look at it.

I haven't given up on repairing the 3 drives that I killed, so far I have replaced numerous caps that couldn't take the ripple I think.
I have the stepping and head loading working but the read/write still doesn't work.
If I get them going I can unlock all the treasures I have in boxes of 8" disks.

If you need help patching the roms for you system let me know.
The D000 - D7FF is identical or near identical to the original so the disassembly listing should match.
The POJ (Power On Jump) still launches the monitor at D000.
 
Cheers Bruce

[someone]

Hi Bruce,

Thanks for making the binaries available and do you know the genesis of these ROMs as they don't seem to be mentioned in any official Applied Technology literature. Someone guesses that it was an enthusiast's pet project just like Gerard Hill's own variant of DGOS for his S100 system which has his signature touches such as the CR ROM character being displayed on the CLI after pressing CR and slightly different memory display routines. (And later for microbee - his high pitched beeps for Telcom!)

What do you use to hold the C000-C7FF and C800-CFFF 2K ROMs? An Applied Tech 16K ROM board or other?

System operation appears to be normal with POJ to the DG680 onboard ROM at %D000 but with the contents of this ROMs having a few adjustments to support and be reliant the 2 other ROMs.

Someone thanks you very much and hopes that you post more S100 and DG680 system related items.

---

Someone just noticed that the ROMS also seem to extend DGOS 1.4 to support fast speed transfers.

[gentle1]

Hi Someone,

I'm not sure of the origin of the monitor roms. 
However I used to belong to the microbee users group that gathered in Burwood, Melbourne and there was a group of us that were quite active and exchanged our code.
It may have been born out of that. If I get to the source hopefully ther will be some credits in there.

I have a 64k memory card that takes 6116 ram chips which are compatible with 2716 roms. No too sure of the manufacturer of the card but I interweave the ram and roms as appropriate.


The fast tape commands change the CTC output clock but you need to make sure your SECI/CUTS board can run at 1200baud.


Cheers Bruce

[someone]

The fast tape commands change the CTC output clock but you need to make sure your SECI/CUTS board can run at 1200baud.

There’s also the later released USCI which is a much smaller board with motor on/off relay (which requires no mods).
If you are able to disable interrupts, have no wait states and patch in some code one doesn’t really need a fancy tape interface because it can be driven by software like the microbee, microprofessor and other computers.

[someone]

I Haven't come across the DG750 I/O card if you have any info I would be interested in having a look at it.

The repository only contains a summary of the board thus someone has tried to contact David Griffiths for more information but until successful all that can be said is that it consists of:
4 x Signetics 2561/2662 USARTs
2 x 8255 PPIs
2 x AM9519 Programmable PIC controller (How many persons actually had or used the DG 680 CPU's PIC or SWP RAM?)

Someone has used Z80 SIO/DARTs and the subsequent SCC for some of their designs because it more easily works with the Z80 daisy chained interrupt hardware. In the 1970's & 80's the Z80 SIO, DART, DMA and some other peripheral ICs were frightfully expensive.

[nauseous]

Howdy All,
Going through some S100 gear and I have found a ROM that alludes to DGOS 1.4.. In a cromemco 32k bytesaver board. I could only read 2 out of the 3 roms that were populated (2716)..
Wanted to compare with whats in repository..

Also in this lot was an ETI640 card...

[ChickenMan]

Hi nauseous and welcome to the forum

What we have in the Repository is referred to as DGOS 1.4+ as mentioned above, a modified original DGOS 1.4. Near the end of rom 3 code it has "DGOS 1.4+ c1983"

The roms are in our MbeeTech\AppliedTech-Pre-Microbee\ROMs folder, so join the Repository here https://microbeetechnology.com.au/forum/...php?tid=15 and see if they compare to the ones you already have.