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Looking for Sord M23P boot disk

J

jltursan

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I'm trying to fully restore an old Sord M23P and after cleaning and heavy lubbing the floppy drives I need to find any kind of bootable disk to finish testing the M23.

Does anyone knows a way to find software for this machine, physical or dumped images?, it doesn't matter what OS: Sord-OS, FDOS, GDOS, CP/M..., if it boots, it's good.
 
Hello,

I’m still looking for a M23 boot disk.

any support will be really appreciated.

Regards,

Franck
 
I'm also still looking for a bootable disk but with no luck. Definitely seems that they're rarer than hen's teeth. I guess that the M23P is totally compatible with the Sord M23 Mark III boot disks; but even being more "popular" I haven't found them either.
Anyway, user arjoll has been working on it past year: https://torlus.com/floppy/forum/viewtopic.php?t=3862. Never tried with M68 boot disks; but maybe is something worth to play with. Hope arjoll is doing well and have continued working with the M23 disks.

Btw, fbal, I can't see your PM bodies so better stay in this thread to communicate.
 
Mmm, that's great news I've missed. It's an IMD image file so you don't really need a Gotek/HxC to try it, just the right setup to write it to a real floppy and test it. As I've a quite capable tweener, I'll try it to create a bootable floppy ASAP. Luckily 3.5" floppies are usually less prone to give headaches so I'm optimistic :-D

I'll get back to post the results...
 
Oh well, first tests failed. I've written the IMD image to several 3.5" DD floppies without luck. Using IMD 1.18 and leaving most of settings as defined by the original source (except double-step set to OFF as this is a 80 tracks image file), the image is flawlessly written to the floppy; but the M23P just tries to read a couple of seconds before locking the machine, no other signs of life.
I've also tried some other combinations, double-step to ON (as the drive is an HD model) or resampling data from 250kbps to 300kbps, IMO not needed because 3.5" drives are also 250kbps capables.
Of course I need to check other combinations. The sord could be also faulty, never seen their drives working so I'll need to diassemble and try to swap or replace them with known working units.

It's gonna be a hard and long work...

Btw, do you known of any M23 emulator?, seems that these machines are far from being emulated yet.
 
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Looking at the Image it's just 16 sectors of 256 bytes times 80 tracks for 1 side. (16 * 256) * 80 = 327680 Bytes
with a sector order of 1 9 2 10 3 11 4 12 5 13 6 14 7 15 8 16

$ IMDA M23.IMD > M23.TXT

IMageDisk Analyzer 1.18 / Mar 12 2012
IMD 1.17: 21/07/2021 16:06:45

File generated by the HxC Floppy Emulator software v2.13.6.12

Required cylinders: 80
Required heads : 1
Data rate : 250kbps
Est. maximum track: 5541 bytes

Possible drives/options to write M23.IMD :

5.25" QD 80-track
Double-step: OFF

5.25" HD 80-track
Double-step: OFF
250 kbps -> 300 kbps

3.5" DD 80-track
Double-step: OFF

3.5" HD 80-track
Double-step: OFF



$ IMDU M23.IMD M23.RAW /B /E /D >> M23.TXT

IMageDisk Utility 1.18 / Mar 07 2012
IMD 1.17: 21/07/2021 16:06:45

File generated by the HxC Floppy Emulator software v2.13.6.12

Assuming 1:1 for Binary output
0/0 250 kbps DD 16x256
1 9 2 10 3 11 4 12 5 13 6 14 7 15 8 16
D D D D D D D D D D D D DE5 D DE5 D
1/0 D D D D D D D D D D D D D D00 D D
2/0 D D D D D D D D D D D D D D D D
3/0 D D D D D D00 D00 D D D D D D D D D
4/0 D D D D D D D D D D D D D D D D
,,,
,,,
,,,
,,,
76/0 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5
77/0 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5
78/0 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5
79/0 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5 DE5
80 tracks(80/0), 1280 sectors (125 Compressed)


Larry
 
Thanks for the extensive info!

Indeed, the drive used has been a 3.5" HD 80-track; so the settings in IMD are from the original source (you listed them above) except "Double-step" manually set to "Off". I've created multiple disks to be sure it's not a media problem; but all of them seems to fail to load anything.

Problems right now are:
- There's no emulation for this machine so I can't test the original IMD image file, I must trust it works fine (the content looks good tho).
- Seems that the original drive is a 5.25" SSQD 100tpi, maybe there's a problem trying to replicate this using any other kind of drive. May I try a 5.25" drive instead the machine's 3.5"?..
- I cannot trust my own machine, floppy drives could be bad or even the hardware setup could be wrong, there're some dip switches (8) and I don't have the slightest idea about their use.

I'll try replacing one of the drives with a HxC, seems to be the safest way to try this image.
 
Mmm...I think I'm having an idea of what's happening. The machine, a Sord M23P (Socius M23P in the US) has twin Sony OA-D31V, 3.5" SSDD 600RPM drive units working at 500kbps when doing DD and 250kbps at SD. I'm trying to dump a 300RPM/250kbps DD image as is and probably is not going to work... :-(
 
I'm dumb and posted too soon without seeing the link, woops. Anyway the disk is at my home and I have the appropriate drive here. I can run some tests if needed
 
Hi, I examined the disk image of BASIC for SORD M23 in the Internet archive.

First, I found the following from this disk image:
1. 80tracks, 1side, 16sectors, 256byte/sector. 2. all sectors are MFM record type.
2. all sectors are MFM record type.
3. 256 * 16 * 80 = 320kByte/disk

Next, I disassembled and analyzed what I thought were the boot sectors (sectors 0-6). I found the following Serial I/O is Z80SIO, Counter is Z80CTC, DMA is Z80DMA, Floppy Disk Controller is unknown, but I think it is MB8877.

FDC is MB8877?
0xc0 : FDC command/status reg?
0xc1 : Track reg?
0xc2 : Sector reg?
0xc3 : FDC data reg?
0xc4 : Z80DMA I/O address

Z80SIO
0xf8 : Z80SIO_A_channel Data reg.
0xf9 : Z80SIO_A_channel Control reg.
0xfa : Z80SIO_B_channel Data reg.
0xfb : Z80SIO_B_channel Control reg.

Z80CTC
0xfc : channel0
0xfd : channel1
0xfe : channel2
0xff : channel3

I don't have a SORD M23, so I can't actually verify it, but once I get the model number of the FDC, more will be revealed.
Knowing the model number of the FDC will allow me to write a small monitor program to the boot sector to get more information.

I have blogged about the results of my analysis of the SORD M68 and M68MX. I hope you will visit my blog.
 
tunozemichan said:
I found the following Serial I/O is Z80SIO, Counter is Z80CTC, DMA is Z80DMA, Floppy Disk Controller is unknown, but I think it is MB8877.
Click to expand...
You guessed right, it's indeed a MB8877.

Here's a list of the motherboard main chips, minus RAM and EPROM. The motherboard revision is M2-CPU-03
  • Hitachi HD46505SP (Video controller)
  • Sharp LH0080A Z80A-CPU
  • Sharp LH0086A Z80A-SIO/2
  • Sharp LH0081A Z80A-PIO
  • Sharp LH0082A Z80A-CTC
  • SORD GA007 MB14384 (Gate array likely)
  • SORD GA002 MB14320 (Gate array likely)
  • Toshiba TMM333P (Mask ROM)
There is also an unpopulated slot for an AM9511 FPU.

In the floppy controller cartridge:
  • Sharp LH0083A Z80A-DMA
  • Fujitsu MB8877 (Floppy controller)
I need to dump the motherboard ROM but I don't have the hardware to read 2532 chips yet.
If you need me to check more things, feel free to ask.
 

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Thanks for all the information, I thought the M23P was similar in configuration to the M68.
If I trust the description on this page about the M23P, the I/O address should also match the M23 exactly. I will continue to analyze the boot sector of the BASIC disk.

Today, I did the following.

Consideration of M23P Floppy Disk Format

The FDD of M23P is Sony OA-D31V. Also, SONY SMC-70/777 (sold only in Japan?) has the same FDD (Sony OA-D31V). By the way, SMC-70's FDC is MB8876.

The FD format of SMC-70 is 70track,1side,16sectors,256byte/sector, so the capacity is 286720byte(280kb).
Wikipedia's article for the M23P states that the capacity of the FD is 290kb; if Wikipedia's description is correct, the FD format for the M23P could be 72 track (288kb) or 73 track (292kb).
Also, the RPM is double speed (600RPM), so if you use FDD emulator, you need to set it properly. FlashFloppy seems to be able to set RPM. The FlashFloppy seems to be able to set the RPM, but I don't know if it can actually emulate 600RPM. HxC seems to be able to set it. This discussion is of course irrelevant when writing to a real FDD.

Creating a boot disk image of M23P

If the boot ROM of M23P is similar to the code of M68, it should read 2kb (0track, 0side, 1-8sectors) at boot time.
You can create a disk with a small monitor program written in these sectors and try to actually boot it.

First, we created a disk image(track70_smc70.img) with the same format as the SMC-70 (70track, 16sectors, 256byte/sector). At the same time, disk images of 72track(72track.img) and 73track(73track.img) were created. All images are raw.

The monitor program I wrote is a version of Universal Monitor with some functions removed.

The experiment of booting M23P

This experiment requires several pieces of equipment.

1. USB to RS232C cable
2. a serial cable adapter (DB9 to DB25?) adapted to the M23P

Connect the M23P to a Windows machine via the above cable, run the appropriate terminal software on Windows, and make the following settings.

9600bps, 8bit, No-parity, stop bit1

The configuration code for the Z80CTC of the M23P was slightly different from that of the M68. If there is no response at 9600bps, try changing the baud rate.

Set up a disk image on the M23P, or physically insert an FD and let it read the disk after resetting.
If you see any text on the terminal screen, you have succeeded.
 
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I'm dumb and posted too soon without seeing the link, woops. Anyway the disk is at my home and I have the appropriate drive here. I can run some tests if needed
Click to expand...

Thanks for the help offer!. The main issue with this image is how to write it back to a floppy like the one in the M23P (Sony OA-D31V, 3.5" SSDD 600RPM/500kbps)...:(

I can only think in replacing one of the drive units with a 5.25" drive using an adapter; this way and with a bit of luck, maybe the Sord could boot and make a copy using the 3.5" drive.
 
I recommend the FDD emulator as a way to use images, GOTEK is a very inexpensive FDD emulator, you can install a great free firmware called FlashFloppy on GOTEK and you can try FDD images.

I also use GOTEK+FlashFloppy to analyze my SORD M68.

By the way, I've been looking for documents on the OA-D31V (M23P's FDD) for the past few days.
I found a useful document, though in Japanese, which I will upload to GoogleDrive; you can try to translate it using GoogleLens or something similar.

If you want to connect a 5.25" FDD to the M23P, you will need an adapter that converts the 26-pin interface of the OA-D31V to the 36-pin interface commonly used for 5.25" FDDs.

Even if you want to connect an FDD emulator to the M23P, you will need this conversion adapter, so you will have to make one anyway.

The pin assignments for OA-D31V can be found in the document I uploaded, so please refer to that.
 
Thanks tunozemichan!, I've already tested Gotek+HxC firmware thanks to an adapter 26-pin to 34-pin without success.
As I don't have a single good real boot disk, I can't assure the FDC in the M23P is working 100%.

The Sony drives in the Sord are the same the ones built-in the Sony SMC-777 or SMC-70 so I can also try first to make the Gotek work with the SMC machine and then, use this knowledge to try again with the Sord...not an easy task all in all!
 
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