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Searching for IBM S/23 Datamaster users

Hello,

I checked the CRTCs and found that were working but the behaviour is different from the stock one regarding the interrupts during initialization. Therefore, I would like to ask for help patching ROM 02 in order to make stock 8275 units compatible with the Datamaster. Please, I would need address of the CRC, its value, and the algorithm to calculate it once the modifications are done.

Thank you in advance!
 
I think I managed to fing the initial vector of the CRC calculation, but for the time being I have deactivated the test.

I need help patching test 05h so stock 8275s can work with the Datamaster motherboard. Please, could someone give some support? If needed I will provide both the original code and my own.

Thank you in advance!
 
I have four units, two of them may be sanded, but the behaviour of the interrupt generation is the same on all them.
At this point I have also bought a 8276 and some KR580VG75. Just for testing purposes.

I am rewriting the test from scratch, but apparently I am missing something.
 
traveler_aa5 said:
I don't know if anyone was aware that IBM made a special machine, based on the Datamaster, just for State Farm insurance. It included a built-in printer. Both the Datamaster and the built-in printer were developed at Boca Raton. We had one in the printer lab, but I never had to work with it.
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Wouldn't you know for any chance the model number, right?
I would be very interested in knowing more about it and find the related documents. This means there would be at least three models of Datamaster!
I am also trying to improve the Wikipedia articles in many languages, so finding information would be very useful.

Thank you very much in advance!
 
RetroAND said:
Wouldn't you know for any chance the model number, right?
I would be very interested in knowing more about it and find the related documents. This means there would be at least three models of Datamaster!
I am also trying to improve the Wikipedia articles in many languages, so finding information would be very useful.

Thank you very much in advance!
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Sorry. I don't remember. It was a LONG time ago.
 
One of the users I contacted has a faulty IBM 5247. We will attempt to repair it. For this reason, I would like to ask all of you who have physical libraries of documentation about the Datamaster if you have the 5247 Service Manual, please.

Thank you in advance!
 
RetroAND said:
One of the users I contacted has a faulty IBM 5247. We will attempt to repair it. For this reason, I would like to ask all of you who have physical libraries of documentation about the Datamaster if you have the 5247 Service Manual, please.

Thank you in advance!
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Right on- somebody finally requested a service manual fir the old IBM 5247 Network drive.
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In the past I tried to contact other System/23 owners who photos of manuals looked like that they had a complete set. But no luck with it.
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So far online only the setup manual can easily be found, nobody has archived a copy of it online into a publicly accessible website.
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Since you are in contact with others who do have a 5247 network drive, may be we can get them to post complete photo of their unit's internal guts as a place to start.
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Do to how this unit internal works, some good photos will let other know what you will be dealing with. Internally these units have their own motherboard with slots and use a somewhat proprietary hard disk controller with a Pro proprietary hard disk and I/F.
 
Updating these units can be an issue due to their design with IBM only parts.
> If the System/23 (also called the Datamaster computer at times) doesn't have the Network card require for this drive, you going to have to recreate it first.
> IBM 5247 network drive hard disk replacement- Is Possible but you need the FSG HD utility disk or a System 36 model 5362 System Unit with the hard disk controller installed for a 21ED xx series of hard disk. Note the Hard disk controller uses a custom firmware rom for drives with over 30Mbyte capacity.
Software: the disaster recovery software, Hard disk Diagnostic and format utilities.
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Hopefully these two entries will help get this ball rolling as the saying goes.
 
It is a great step forward. I will use the opportunity not only to learn about the 5247 but to learn how it works so a similar device can be made in order to save and load programs from the main computer without having to rely in the 8 inch disk floppy drives, which are starting to fail.
 
RetroAND said:
One of the users I contacted has a faulty IBM 5247. We will attempt to repair it. For this reason, I would like to ask all of you who have physical libraries of documentation about the Datamaster if you have the 5247 Service Manual, please.

Thank you in advance!
Click to expand...
Your entry does not really state what the faulty drive symptoms are, so without access to the manual and/or its symptoms posted a lot of help might be excluded from any reply's. Do to the complexities of the 5247 external networkable Hard disk unit.
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Is there a copy of the OEM drive manual anywhere?
The drive has two boards, one contains an Intel microcontroller and the other is the read/write channel
I've never come across FE manuals for the 5362. The 5360 is much better documented in the files on bitsavers.
There are some pictures of the 21ED drive under dasd/21ed there as well.
 
Ya trying to find a copy of the 21ED drive manual that is on a publicly accessible archive is going to be an issue. Some system/36 service (FE) manuals some time had it included if the drive was sold installed in the system depending on what the client ordered and purchase.
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The IBM 21Ed general information manual part number is SY31-9002 and hopefully some forum user reading this message has a copy and they are willing to scan it. And then upload a copy of it to bitsavers as well.
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Inside the 5247 the controller motherboard and its hard disk adapter documentation might be another issue as well. I guess in time we will see what happens to show up.
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Thanks'
 
Al Kossow said:
Is there a copy of the OEM drive manual anywhere?
The drive has two boards, one contains an Intel microcontroller and the other is the read/write channel
I've never come across FE manuals for the 5362. The 5360 is much better documented in the files on bitsavers.
There are some pictures of the 21ED drive under dasd/21ed there as well.
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Thnk's for replying
 
If you want to see the insides, you can check the WDA forums: https://wda-fr.org/forum/viewtopic.php?t=766
Basically, a structure similar to a 5324, with similar looks. It has a motherboard similar to the System/23, with DRAM on boards (different from the ones from the S/23) and a communications interface to connect with the Datamaster.
I expect the microprocessor to be an 8085 and maybe even the board itself could be a byproduct of the System/23 arquitecture (speculation).
EDIT: it carries a 62-pin card-edge connector, maybe the same pre-ISA the Datamaster brings.
 
By the way, I received an American Datamaster boards I am restoring them to a functional state. I may even mod it to comply with the European video signals. It carried two 32KB boards, but I think I will just leave it with one and bring the second one to the complete unit to fit it with 96KB DRAM. The American board only has one clock and seems to mostly work. With just a few adjustments and repairs, I think I can bring it to a fully functional state. Then, with the composite video adapter I made back when I started to work with this kind of machine, I will use it as a test unit to develop spare parts such as memory boards.
 
Just a Couple of photo of a IBM 5247 drive. One Inside shot and one of the back side.
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DISK STORAGE: The 5247 disk storage unit is a floorstanding fixed disk unit, as shown in the drives setup manual.
The 5247 was available in two models at one time:
> Model 011 has a storage capacity of 15.4 megabytes. Average access time is 40 ms.
> Model 012 has a storage capacity of 30.8 megabytes. Average access time is 40 ms.
> Model 013 and above, I sorry to note that their is no currently publicly accessible data for them : 60M plus units.
= Old models 01 to 10 I leave omitted for now.
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In general the standard 5247 Models 011 and 012 may attach to one or two Datamasters. An adapter extension (IBM profile #3700)
allows a third and fourth System/23 computer to be attached to the 5247. Three Datamasters may be located up to 1000
feet in distance; one computer must remain adjacent to the 5247 for servicing use.
The 5247 is file format compatible with System/23 Datamaster diskettes but the units interface a network type drive.
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Backing up the Sys/23 (Datamaster) via MAGNETIC TAPE: None currently available from IBM, but at one time 3rd parity units did exist.
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Service manuals for the the 5247 Network drive where once found System 23 (technical) Service manual library.
The 5247 Disk unit is described in Volume 6 if there in the IBM System/23 Service Library.
External 5246 Diskette unit was in Volume 4 of this documentation set.
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Old 3rd parity alternative to this/theses units where available at one time, But trying to find a complete working unit is mostly impossible now days.
Core International, PRAIM, SunOl, Corvus. Some of these used a custom control and adapter board with special software Like Tallgrass.
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For a replacement 30MB 21 ED drive refurbished yes a 30M 21ED drive with a 90 day warranty are still available (as of Thursday April 24 of 2025 at 5:21pm)
from : https://www.tamayatech.com/parts.php?g=1616699&gid=337496 for about $107.00 in U.S. Funds plus transportation and import cost, so I would not
bother with the scalpers on ebay.com in this case for a truly questionable drive.
 

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Another easy alternative to the IBM 5247 would be to modify another old network or serial port external hard disk unit.
> If you can find an old well documented Serial Port based Network drive that supports Sync communications- This will take some programming and other skill to get it to work.
>Old School Modification Of serial port Mac Based external hard drives. The two closest units to this drive would be the Tecmar MacDrive or the old Davong MacDisk
as they are both high speed serial SNA/Bisync protocols like devices. To do this you will be writing new firmware and system drivers plus wiring up an adapter cable.
Both of these drives will support none Macintosh Hard Disk Volumes if you have the equitant software diskette. (PRODOS, CP/M, MS-DOS, UNIX MC68K, etc.)
> New School, a long process use a newer MCU development board that supports SNA/Bisync protocols.
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There are a lot of Corvus drives still listed for sale on websites like Ebay.com but the host Controller/adapter and the software is missing for system like the Datamaster.
The bandwidth on these drive are also limited if there are not Omninet 4 or greater compatible.
 
"the software is missing for system like the Datamaster."

That would be the problem. I've been collecting Corvus stuff for decades and up until your
post I didn't even know Corvus disks were supported on the Datamaster.
 
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