• Please review our updated Terms and Rules here

Booting an IE EQ4 with someone else's CPM System disk?

falter

Veteran Member
Joined
Jan 22, 2011
Messages
6,556
Location
Vancouver, BC
Thanks to the generous provision of information by paggps, I now have enough info to potentially boot my Insight Enterprises EQ4 board.

That said, I have had no luck finding images of the system disk for this machine. I am wondering.. is it possible another CPM system disk might boot it? I presume not.. given you'd need the exact same IO configuration?
 
Do you happen to have the Disk Parameter Block (DPB) Information for that system? Or will it boot to a Monitor that you can probe
Memory?

Larry
 
Hi Larry.. that stuff is a bit over my head - what I do have is what paggps provided. I looked at the disk drive info and it's a bit over my head also.

From the documentation all I can figure out is that the machine could function in either serial or direct video/keyboard input mode, and that IE gave you CPM 3.0 system disks. I've been looking around for Insight EQ-4 CPM disks but nothing comes up.

https://drive.google.com/drive/folders/14F3XUYUuqusBRFkQCx1NGvkbZZdWmFc8?usp=sharing
 
That's a pretty awesome machine. If there are no CP/M images out there for it, then it's going to require someone creating a new CP/M BIOS for it. If there are no schematics, then you're down to disassembling the ROM and trying to infer hardware from that. No small task, but it is a pretty impressive machine.
 
Doug will you double check my DPB numbers? I think they are the following according to the ROM:

Code:
40 Tracks = 0x28

000002C0 0F 15 02 08 0E 14 1A 06 0C 12 18 04 0A 10 16 [B]28 [/B]...............(
000002D0 00 04 0F 00 8A 01 7F 00 C0 00 20 00 02 00 03 07 .......... .....
000002E0 00 FF 50 00 7F 00 FF 74 00 01 00 09 40 00 00 00 ..P....t....@...


The Disk Parameter Block (DPB) for each drive is:
+-----+------+-------+-------+-------+-------+------+------+------+-----+
|SPT.|BSH..|BLM..|EXM..|DSM.. |DRM.|AL0..|AL1..|CKS..|OFF.|
+-----+------+-------+-------+-------+-------+------+------+------+-----+
16B 8B 8B 8B 16B 16B 8B 8B 16B 16B
Code:
RPT = 0028 = The number of 128 byte records per track = 40
SSZ = ^^ = 128 bytes per sector
BSH = 04 = The block shift count = 04
BLM = 0F = The block mask = 15
EXM = 00 = The extent mask = 0
DSM = 018A = Disk storage maximum (the largest block number) = 394
DRM = 007F = Directory maximum (the largest directory entry) = 127
DAB = C000= Directory Allocation Block AL0: = C0 & AL1: = 192 0
CKS = 0020 = Directory check size = 32
OFF = 0002 = Track offset (number of reserved tracks) = 2

SPT: Number of sectors per track. May differ from RPT if physical sectors are other than
128 bytes in size.

SSZ: Sector size code:
0 = 128 bytes per sector
1 = 256 bytes per sector
2 = 512 bytes per sector
3 = 1024 bytes per sector

Larry
 
That does look like a CP/M 3 DPB in the ROM code, which would suggest that the ROM implements part of the BIOS. This is also implied by the fact that the ROM copies itself into high memory. Disassembly and analysis should reveal the API, which would drive the BIOS. Depends on how complete the ROM is, though. It does only contain less than 3K of code, but perhaps that's enough. Is there only one DPB in the ROM?

The DPB tells me that this is for an 80-track, two sided, drive using 1024-byte sectors, 5 per track. The floppy controller looks to be quite robust, and probably is connected to the Z80-DMA channel(s) - which should simplify the code a lot. The CP/M format uses 2K allocation blocks, and reserves two of those for the directory - and uses all of the reserved space for the directory. It also reserves two tracks, presumably for the boot image.
 
Doug,
I stopped looking after I found the first DPB, so I'm not sure. I got an email stating the IE should boot from a Wave Mate Bullet Boot floppy.
Next step is to get Don the emails and let Don go from there.

Thanks.

Larry
 
Did a little "recreational disassembly" of the ROM. It does not appear to be anywhere near a complete CP/M 3 BIOS, however it is heavily structured towards that. It has handlers for CP/M 3 character I/O redirection vectors, but only supports device output. It has some CRT handling code, but does not seem to support any sort of advanced features (ESC sequences, etc). If this code is still used once CP/M 3 boots, I suspect it has a great deal added and modified. It would also suggest to me that a lot of the code on the CP/M boot tracks is specific to this hardware (i.e. the ROM does not have enough code to handle the needs of a CP/M 3 BIOS).

Based on what I can glean from the photo and ROM code, and information available on the WaveMate Bullet, I'm not sure they are compatible. They have different floppy controller chips, which don't appear to be software compatible. I don't believe the WaveMate has any built-in CRT hardware, either. The Z80-DART I/O ports also don't seem to be the same.
 
A little more digging shows 4 DPBs in the ROM, and it appears that some dipswitches (or jumpers) configure which one is used to boot. There are:

5" DD/DS/DT 800K
8" SD/SS IBM-format
8" DD/DS 616K
5M HDD of some sort

There is a setup of DPHs and a 16-drive DPH table, however they are not configured as one would expect a CP/M 3 system to be run, so - again - I suspect this CP/M 3 skeletal structure is configured for booting and not for normal system run - i.e. once booted, the CP/M 3 cold start code reconfigures things.
 
So others can see your previous discussion about this board:
https://www.vcfed.org/forum/forum/t...1-insight-enterprises-z80-sbc-powerup-attempt

As you mentioned above, user "paggps" provided a Google Drive link to a lot of information he had on this board. He provided a folder named "Firmware Sources" in which he provided the assembly source for several programs that I thought he had developed for the EQ4 board including:
- the ROM boot loader
- a Format utility for IBM 3740 SS/SD 8" disks
- a BIOS
- floppy controller drivers
Admittedly I have not done a detailed review of these assembly sources - but it seems what "paggps" provided would help answer many of your questions. You would still have to do a fair bit of additional work to create your own 8" boot disks from scratch. Do you have another functional CP/M system with 8" drives that you could use for development of your own CP/M boot disk?
 
Unfortunately no.. the only CP/M machines I have that even would have used 8" drives would be my Xerox 820s but I don't have the drives for those. I have a TRS-80 Model II that has 8 inch.. thats the only machine in my collection that actually has the drives.

I actually have the three drive expansion unit for that.. not sure if it's compatible with other systems.
 
Most/all micros with 8" drives supported the "standard" IBM-3740 SS/SD format, specifically for data interchange with other micros (and possibly mainframes). I'm not very familiar with the TRS-80 line, but if you have CP/M then you might be able to use SYSGEN.COM to write an EQ-4 boot image to a SS/SD floppy, and boot it on the EQ-4 (with proper jumper settings). That depends on how generic the TRS-80 SYSGEN.COM is. Worst case, writing a CP/M program to put the image onto a diskette is not that difficult.

The information from paggps looks like it will be enough to create a bootable image - although I have not sifted through all that yet to see what else, if any, needs to be written.
 
Unfortunately no.. the only CP/M machines I have that even would have used 8" drives would be my Xerox 820s but I don't have the drives for those. I have a TRS-80 Model II that has 8 inch.. thats the only machine in my collection that actually has the drives.

I actually have the three drive expansion unit for that.. not sure if it's compatible with other systems.

I would expect those 8" drives to be universal, but one can never be certain until you examine them.
 
I have a TRS-80 Model II that has 8 inch.. thats the only machine in my collection that actually has the drives.
I actually have the three drive expansion unit for that.. not sure if it's compatible with other systems.

Based on information I was able to find about the TRS-80 Model II, the built in 8" drive was a standard Shugart SSDD drive and the expansion unit used standard CDC 9404 SSDD drives. Configuration manuals for these drives can be found on other web sites. Assuming you would be using one or more drives in the expansion unit (rather than removing the drive in the TRS-80 Model II), you will at minimum need to change the drive select jumpers.
 
Hi Larry.. that stuff is a bit over my head - what I do have is what paggps provided. I looked at the disk drive info and it's a bit over my head also.

From the documentation all I can figure out is that the machine could function in either serial or direct video/keyboard input mode, and that IE gave you CPM 3.0 system disks. I've been looking around for Insight EQ-4 CPM disks but nothing comes up.

https://drive.google.com/drive/folders/14F3XUYUuqusBRFkQCx1NGvkbZZdWmFc8?usp=sharing
Hello falter,
Just popped in again to check what was going on to your EQ-4 project.

It is coincidence that the problem you are facing today (the lack of a bootable CPM disk) is the same problem I had in 1984/1985. When I bought the EQ-4 board at that time, the CP/M disks were damaged (or I damaged them, I don´t remember). I could bood perfectly for the first time, but after that I could not boot again, probably because I was playing with the machine using the original disks before doing a backup. This error would cause me anormous headaches. This is what I did at that time, just in case it might help (exact steps ... I don´t remember because it was almost 40 years ago):

1) I wrote my own boot EPROM to create a very basic bootable machine, that could read SS/SD floppy disks, and do the basic things like read keyboard and write to video (I think this is the file bootrom.asm in my repository, not 100% sure).
2) I wrote also a small program to format 8" SS/SD disks (this is the file format.asm), and also another program to read/write individual sectors on the disk (this is the file rwd.asm)
3) Using an RS-232 cable, I managed to transfer the CP/M 2.2 boot files to the EQ-4 from an Apple II I had (it was an Apple II Plus with the Microsoft Z80 card on it). This step would not be neccesary today because CP/M 2.2 images can be found anywhere.
4) Using rwd.asm, I was able to write the CP/M 2.2 files (sectors) to the newly formatted disk.
5) After that... magically, the new disk with CP/M 2.2 booted perfectly, and I used the machine for a lot of time.

In parallel to this work, I kept looking for an original full CP/M 3.0 bootable disk from another user (Insight Enterprises was bankrupt, and I have read its know-how was sold to a mexican company). Then I published an ad in the BYTE magazine (August 1985) asking for help. I received about 7 letters, and finally one user (I remember Mr. Toby Popenfoose) sent me a bootable CP/M 3.0 complete with sources. So I changed EPROM to the original one, and then the machine was working in full, and was used for years.

By the way,
- One of the persons that answer my ask for help in 1985 was Mr. Victor Roberts. I found him in Linkedin and asked (again) if he has something related to the EQ-4. He just donated it to a technology museum, and offered me to try to obtain a copy of the bootable disks. Then came the pandemic. So I don´t know...
- Looking into the documentation I have, I see that the person who wrote the EQ-4 code is Mr. Ralph Nicovich (71). Googling it you can find that he is still related to computer science in the San Francisco area. Perhaps he still has something...

Sorry for such a long post. Best of luck !
Regards,
Pablo
 
Back
Top