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CompuPro DISK1A boots but not with CPU 286 card

retrogear

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Minnesota
I have been searching for a DISK1A floppy controller for my CompuPro 8/16 for almost 2 years until I recently purchased one on Ebay. I had to solder in 3 7805 regulators to convert the power for my system. I just got it to boot Concurrent CP/M 3.1 !! Here is a video: https://youtu.be/_huYgwB1p9A

I have been using a 8085/88 cpu but now I was hoping it would work with my CPU 286 board I got with the system but still no go :(
Here is a photo of the board. I don't see any jumpers to configure? The ROM on my DISK1A is 291B. It does seem to engage the drive when I press reset so I think the cpu is running?
CompuPro 286.jpg

Fun stuff !!

Larry G
 
To boot a Compupro 286 processor board on a Disk-1A might take a different Boot Rom Switch Setting than a 8085/8088 dual processor board, depending on what switch settings are set on the Disk-1A, and which version of the Loader Program you have on the hard drive and/or the 8" floppy boot disk.

There is a 8-bit boot setting on the Disk-1A for use with a floppy drive and the 8085/8088 processor board with a version of CDOS 3.1. There is also a 16-bit boot setting on the Disk-1A, and a separate version of CDOS made for booting 16-bit processors like the 8086 and 80286.

If you have been booting CPM-80 and CDOS with the same switch settings on the Disk-1A, then you probably have the Disk-1A set for a 8-bit boot. You will need to reset the Disk-1A switches and the Boot Loader for a 16-bit boot.
 
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Got it !!!

It's kind of a chicken and egg problem because things have to be configured from the running 8085/88 processor system before switching to the CPU 286 board.
I copied CCPM340.SYS to CCPM.SYS on the hard drive and copied LDRCCPM3.86 to the HD, then you have to run SYSGEN from the floppy drive I: to the hard drive A:
(it won't let you commit suicide by sysgen-ing the drive that's logged in)
0I>sysgen a:ldrccpm3.86
destination disk? a

Then I pull out the 8085/88 card and put in the CPU 286 board and set the DISK1A S1 #3 from ON to OFF and it boots from the hard disk !!! Here's a video of the boot:
https://youtu.be/k7vor_FoMVU

fun stuff !!

Larry G
 
It's not complicated to come up the first time when you have the Original Compupro Masters for 3.1 or 3.1DM. 8-bit boot Loader is sysgened on Disk #1 and 16-bit boot is Loader sysgened on Disk #2.

Set the switches on the Disk-1A for the processor that you are running, power up the mainframe and the disk enclosure, hold the RESET Button on the mainframe while inserting the Disk that has the appropriate Boot Loader.

Version 4.1 and higher have batch routines on the Master floppy disks to transfer the necessary files to the User's Choice of a 5.25" or 8" or hard disk drive with the files automatically moved to standard locations (User Areas and Drives) for the Compupro Applications and Utilities Files to create a bootable CDOS System.

If you haven't noticed already, CDOS comes up noticeably much faster with the 286, than it does with any of the dual -processor boards. Have you set your SW! program yet? Do you have a SPU-Z 8mhz Z-80H slave processor board, or are you running the EM8080 8-bit emulator since you don't have the Dual Processor board in the system anymore?
 
>It's not complicated to come up the first time when you have the Original Compupro Masters for 3.1 or 3.1DM. 8-bit boot Loader is sysgened on Disk #1 and 16-bit boot is Loader sysgened on Disk #2.
I read that in the docs but my copies weren't that way.

>If you haven't noticed already, CDOS comes up noticeably much faster with the 286, than it does with any of the dual -processor boards.
Yes I did notice that. Boots in a flash !!

>Have you set your SW! program yet? Do you have a SPU-Z 8mhz Z-80H slave processor board, or are you running the EM8080 8-bit emulator since you don't have the Dual Processor board in the system anymore?
Hmmm - haven't thought about that yet. I have two CPU-Z boards, one is 458B from 1985 and the other is marked 160K from 1981. Would one of these co-exist with the CPU 286 board?
 
>It's not complicated to come up the first time when you have the Original Compupro Masters for 3.1 or 3.1DM. 8-bit boot Loader is sysgened on Disk #1 and 16-bit boot is Loader sysgened on Disk #2.
I read that in the docs but my copies weren't that way.

>If you haven't noticed already, CDOS comes up noticeably much faster with the 286, than it does with any of the dual -processor boards.
Yes I did notice that. Boots in a flash !!

>Have you set your SW! program yet? Do you have a SPU-Z 8mhz Z-80H slave processor board, or are you running the EM8080 8-bit emulator since you don't have the Dual Processor board in the system anymore?
Hmmm - haven't thought about that yet. I have two CPU-Z boards, one is 458B from 1985 and the other is marked 160K from 1981. Would one of these co-exist with the CPU 286 board?


No, both the 160K and the 458B are both Master Processor Boards. You cannot install either of those Processor boards in the system at the same time as the 80286 board is installed. Compupro manufactured both Master Processor Boards, and Slave Processor Boards. Masters cannot be used as Slaves, and Slaves cannot be used as Masters. Control of the bus is switched between Masters and Slave Processor Boards according to IEEE-696 Specifications.

The 160K is a 1st Generation Z-80A/Z-80B board capable of running 2-6mhz. It is Imsai Front Panel Compatible. The 160K is the most common and most successful of the Compupro Z-80 processor boards. The 458B is a IEEE-696 2nd Generation Z-80H Processor board with a 8mhz Z-80H onboard, not Imsai Front Panel Compatible. A very fast board, it may require some speed modifications to the original Compupro support boards for reliable operation. Also requires wait states with all but the fastest Compupro memory boards.

Compupro manufactured two Slave Processor Boards. The SPU-Z was a 8-bit 8mhz Z-80H with dual onboard serial ports (early versions of the SPU-Z were single-user and 64K only, you could only run one in a system) and either 64K or 256K of dram (single user or four-user slave processor), and the SP-186 16-bit 10mhz 80186 with dual onboard serial ports and 512K of dram (two-user slave processor). Users on Slave processors could have Console I/O on the onboard serial port (unloading the main processor), or use a System I/O port such as available on a Interfacer-3 or Interfacer-4, or SPIO.

CDOS was set up to run up to eight of each of these slave processor boards, addressed as a 64K window (a single 64K block for the 8-bit slaves and a single 64K block for the 16-bit slaves) at the top of the 1st 1Mb block of memory.

I've been running three Ram-22 256K static memory boards, and one Ram-23/128K static memory board for a total of 896K of main memory to make the necessary 128K hole for the slave processor boards, since the Early-1990s. I'm getting ready to switch back to a single Ram-24A 1Mb static ram board to save three S-100 slots, some power, and get some heat out of the mainframe ((1) memory board with (1) 5V TO-220 regulator, to replace (4) memory boards with (11) 5V TO-220 regulators).

CDOS includes three switch programs for 8-bit slaves SW!XXXXXX (8085, EM8080, SPUZ), and the 16-bit switch for SP-186 slave processor boards.
 
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Good info - thanks. I didn't know there were processor boards designated as slaves. I'll probably just stick with a 16 bit '86 system for now. I never dreamed I'd get the 286 running. I had to solder 3 7805's on it plus 3 more on the DISK1A.
My next challenge will be trying to get a 5.25 drive running on it. Is there info on what mini drives were used on CompuPro ?
 
Mitsubishi M4853 96TPI 80-Track 720K double-sided 5.25" minifloppy drive.

It was the only 5.25" mini-floppy drive supplied by Compupro (My Compupro Dealer Wholesale Price Lists did show that Compupro did offer a 1.2Mb 5.25" mini-floppy as an Option, but I never saw one installed, or ordered one, or sold any). The M4853 was a good drive used OE by several other computer manufacturers. Kinda scarce on the used market (I see used ones selling occasionally on eBay for $50-$100, As-Is). I sell them (when I can get them), used, aligned, and tested for $200 each with a six-month warranty, or $300 for a new drive with a six-month warranty.

I recently took a look on eBay and all of the M4853 drives that I saw were mistakenly described as 360K drives, and As-Is. That does not bode well for the chances of them actually working.

I charge $100 (plus parts, & return shipping) to fix them, if you should happen to have one that needs repair.

Some people have used a Teac 3.5" 80-Track 720K in place of the Mitsubishi M4853. I sold several cases of Teac 3.5" 720K drives for this purpose. The ones that work are early versions that have four drive select lines/jumpers (late Teac 720K 3.5" drives only have two drive select lines/jumpers and don't work with the Disk-1A).

You will have more trouble finding the correct 96tpi 5.25" mini-floppy disk media (not 48TPI media, and not HD 1.2Mb media) then getting the M4853 drive working on the Compupro (get working drive with power supply and a straight through 34-conductor cable (no IBM twist), set jumpers on Disk-1A). I've found that 48TPI media usually works fine.
 
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FWIW, my friends at Dysan told me the only difference between their 100/96/48 tpi 5.25" DD media was the difference in certificaiton. No difference whatever in the brown goo.

FWIW, I have a NOS (or nearly so--still has the price tag) M4853. I'll happily trade it for a Micropolis 1115-VI 100 tpi model.
 
Wow I didn't know it would be that peculiar. Hmmm I have a Sperry UTS-30 with 720k 96 tpi drives. I know what you mean about media. The 1.2M HD type floppies won't work but the 48 tpi format 720k just fine. I wonder what model of drive is in there ...
Well, I won't sacrifice my Sperry, though ...
 
To recap this thread.

Question from me:
>Is there info on what mini drives were used on CompuPro ?
Answer from our expert:
>Mitsubishi M4853 96TPI 80-Track 720K double-sided 5.25" minifloppy drive.
So I decided to open the drive cage of my sacred Sperry UTS-30. I'll be damned ...
Sperry drives.jpgSperry M4853.jpg
 
I almost asked for help on this but got it working. To get a 5 inch drive working on the DISK1A I had to move J1 and J2 to the 5 position, remove J7 and put the drive select on the Mitsubishi M4853 on DS2 (choices are 0-3)
Now it works well as drive K:
Compupro 5in K.jpg
 
I almost asked for help on this but got it working. To get a 5 inch drive working on the DISK1A I had to move J1 and J2 to the 5 position, remove J7 and put the drive select on the Mitsubishi M4853 on DS2 (choices are 0-3)
Now it works well as drive K:
View attachment 34823


Compupro assembled and sysgened preassembled versions of CDOS 3.1 to support two 8" floppy drives and two 5.25 drives (one minifloppy (drive K:) and one 10mb tape backup drive (drive L:) controlled by the disk controller board). CDOS 4.1 also supported the 10mb tape drive, and CDOS 5.0 and later supported a 40Mb SCSI tape backup drive controlled by the System Support-2 multi-function board (installed in place of the System Support-1 board).

You can reassemble CDOS to support two 5.25" minifloppy disk drives, and later versions of CPM-80, CPM-86, & CCPM-8/16 came setup for two each 5.25" (K: & L:) and 8" floppy drives (I: & J:).

I usually have my Compupro configured with two Mitsubishi M2896-63 half-height 8" dsdd floppy drives, one Mitsubishi M4853 720K half-height 5.25" drive, one 10Mb 5.25" half-height tape backup drive, and a 80Mb CDC MFM 5.25" full height hard disk drive. I'm thinking about rearranging the drive configuration in the drive bays to fit a 2nd CDC 5.25" full height hard disk drive. I already installed power supplies which are capable of supporting the additional drives All I need to do is get a 2nd hard drive, and install the brackets to reconfigure the drives within the two Disk Drive Enclosures.
 
Wow it's been 2.5 years or so. I did recently get a CompuPro SPUZ slave Z80 board and got it to run 8 bit apps. I also found out that user MicrocomputerSolutions who had been so helpful passed away last June. I was wondering why he hadn't responded to my recent PM's. We're losing more knowledgeable people as time goes on. It would be nice to get TurboDOS running on this since I have master/slave capability now. I would need to either find or build a serial cable to connect the SPUZ to a terminal. Anyone know of such a cable or wiring diagram? I made a video demonstrating how to switch and use the SPUZ to run 8 bit apps. It involves the commands spz.cmd and sw!spuz.cmd
https://www.youtube.com/watch?v=paHMmI3fpEQ

Larry G
 
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