Decmation D100Q Qbus Z80 coprocessor board

[cliffmiller]

Purchased one of these online. The installation and support manual is available but no software. Does anyone have experience with one of these?
The software package included CP/M and utilities.

 

[NeXT]

Yeah I saw that listing on ebay as well. Everyone I asked didn't have anything.

 

[pbirkel@gmail.com]

The installation and support manual is available but no software. ... The software package included CP/M and utilities.

I was sent the three RX02 files in the attached ZIP a few years ago but have not yet explored them ...

 

[sunscreen]

I saw the ebay listing and knee-jerk hit buy without checking whether the software was available. Thanks for posting it here! (and fingers crossed it's in that zip file)

 

[NeXT]

By the sounds of it, the seller listed more of them at a higher price, but they came complete with the board, software, documentation AND schematics. Someone's working on archiving that now.

 

[nigwil]

Has anyone found the D100Q software for RSX-11M?

 

[glitch]

I bought one of the more expensive packages from the seller and did get a pile of documentation, but I believe the still-sealed software packet is just a Digital Research distribution diskette with license. I haven't dug into it and started scanning yet.

 

[Ragnarock]

Tell me about this board, is it basically a Z80 CPU that fits in an LSI-11 bus and uses DEC serial port, memory?
What does it do for FD? RX01 SSSD system?

 

[Ragnarock]

I was sent the three RX02 files in the attached ZIP a few years ago but have not yet explored them ...

What are the format of these disk files? The extension gives no clue.

How would these files be read them to create disks? Or write an RX02 disk to create these files?

Imagedisk won't do M2FM RX02 disks.
Greaseweazel??

 

[pbirkel@gmail.com]

What are the format of these disk files? The extension gives no clue.

"_sd" apparently means means "single density. The readme.txt stated:

Decmation 100Q Z80 Support Floppies
RX02 disks imaged with PDP-11GUI
Disk 1: RT/11
Disk 2 and 3: CP/M

Further notes: "Use pdp11gui and a pdp-11 to use an rx02 to write the first disk image. The second and third are CP/M disks, so not sure if the writing from pdp11gui will work. You only need the first disk to test and use the 100Q, after that any 8" cp/m disk should work."

Attached documentation tells (most) all.

 

[Ragnarock]

"_sd" apparently means means "single density. The readme.txt stated:

Decmation 100Q Z80 Support Floppies
RX02 disks imaged with PDP-11GUI
Disk 1: RT/11
Disk 2 and 3: CP/M

Further notes: "Use pdp11gui and a pdp-11 to use an rx02 to write the first disk image. The second and third are CP/M disks, so not sure if the writing from pdp11gui will work. You only need the first disk to test and use the 100Q, after that any 8" cp/m disk should work."

Attached documentation tells (most) all.

I'll have to dig further. RX02 is double density. RX01 is single.
I have yet to figure out how to use the PDP11GUI program everyone talks about on my working PDP11/23.

If the individual files were just made available I could transfer them with Kermit in no time. Except the boot tracks.

 

[Bitly]

In theory you could use PUTR to extract the files from the image. I did it many years ago to read some 11/780 console floppy images, but the exact how is lost. I used QEMU or DOSBOX to emulate MSDOS and run PUTR.

CW

 

[DDS]

I'll have to dig further. RX02 is double density. RX01 is single.
I have yet to figure out how to use the PDP11GUI program everyone talks about on my working PDP11/23.

If the individual files were just made available I could transfer them with Kermit in no time. Except the boot tracks.

"RX02 is double density. RX01 is single."

Not exactly.

The RX02 is a hybrid of the two. Single density formatting with double density data written into the sectors.

There is probably more to it than that but that's the gist of it.

_______

RX01/02 floppy drive - Computer History Wiki

gunkies.org

"The drives are essentially identical, except that the RX02 supports optional double-density operation. This double-density is not the same as the 'normal' double-density 8" floppy, but a unique-to-DEC format. Single-density recording uses a double frequency (FM) coding (compatible with IBM 3740 devices), and double-density uses a modified Miller code (MFM - below).

In an somewhat unusual design choice, on both single- and double-density media, the sector headers are recorded using FM coding, but on double-density media, the data portions of sectors are recorded with MFM."

-------

Even that is not entirely correct as both the RX01 and the RX02 use the same IBM 3740 single side single density media, formatted as an IBM 3740 would, the RX02 just writes the data differently.

 

[Hunta]

Files from DECMATION_100Q_DISK1.rx02_sd

 

[pbirkel@gmail.com]

Files from DECMATION_100Q_DISK1.rx02_sd

Thanks! For the record how did you accomplish this feat :-}?
Could you do the same for the other two disks?

 

[Hunta]

how did you accomplish this feat

This is not a feat, this is my program ImageUtils

ImageUtilX -unpack DECMATION_100Q_DISK2.rx02_sd @DECMATION_100Q_DISK2.rx02_sd rx01 rt11

Could you do the same for the other two disks?

For the other two disks - (at least) not yet - the program does not know how to work with CP/M FS.

 

[glitch]

This double-density is not the same as the 'normal' double-density 8" floppy, but a unique-to-DEC format. Single-density recording uses a double frequency (FM) coding (compatible with IBM 3740 devices), and double-density uses a modified Miller code (MFM - below).

Is the data section of an RX02 MFM or M2FM? I think I remember reading that it's often mis-identified as M2FM but is in fact regular old MFM ("Double Density"), just the mixed density in the tracks make it unreadable by pretty much all other floppy systems.

 

[DDS]

Is the data section of an RX02 MFM or M2FM? I think I remember reading that it's often mis-identified as M2FM but is in fact regular old MFM ("Double Density"), just the mixed density in the tracks make it unreadable by pretty much all other floppy systems.

That was what I quoted from that gunkies.org page. The consensus seems to be that RX02 is readable by some non RX02 stuff, like a greaseweasel, but that doing so is not at all straightforward. Truth be told, a lot of the lower level stuff "exceeds the dimension of my comprehension."

People. including me, read stuff on the web that they don't really "grok to fullness*" then repeat it as gospel, included mistakes and all. But I'm pretty sure that someone who knew their way around a greaseweasel could look at the flux transitions captured from an RX02 and tell what was going on.

But that person isn't me. It's 08:00 here and I'm having trouble spelling greaseweasel.

grok

 

[glitch]

That's what has kept me from getting the pile of RX02s from Mount Washington Observatory imaged -- I have to use the RX02s to do it, and getting a 2.11BSD system finalized to do that has been a multi-year yak shave! Can't use vtserver due to a bug where it reads past the last block forever...

 

[Ragnarock]

That's what has kept me from getting the pile of RX02s from Mount Washington Observatory imaged -- I have to use the RX02s to do it, and getting a 2.11BSD system finalized to do that has been a multi-year yak shave! Can't use vtserver due to a bug where it reads past the last block forever...

Mr glitch, I have recently restored a PDP11/23 in the form of an SMS DSX11 with the ability to read and write RX01 and RX02 disks. SMS has their own controller to do both these formats along with IBM1, IBM2. This system also has an operational KERMIT11 so I can transfer things at the file level to my Windows machine. This option is easier in a lot of cases than battling disk images. So I offer this service to you if you want to preserve some old data. I have an operating imagedisk system with 8,5.25,3.5 drives too.

RogerArrick.com - Scientific Micro Systems SMS DSX11 PDP11/23 Calay PCB Computer 1986

www.rogerarrick.com