Wanted: Microchannel / MCA Adapter

[tgunner]

I need a Microchannel 50-pin SCSI Adapter, or a Microchannel IDE adpter for an IBM Model 70. Or maybe, a replacement hard drive for the original 60 Mb one. I'm not quite sure of what its connection type is, kind of an MFM looking system. Must be cheap, or free.

 

[Terry Yager]

Esdi.

--T

 

[tgunner]

So the original hard drive is an ESDI? Will any ESDI work? I mean, IBM is pretty proprietary, they have a special rail / swappable system, no specific power connector. I'm guessing that the Hard Drive is the problem. When I turn the machine on, it does the ram check, gives 1 or 2 errors, usually relating to the battery, I think 161, 162, or 163, and then moves to IBM Basic. Referance disks won't work, and DOS can't see any fixed disc.

 

[Micom 2000]

Yeah the 16x errors are likely the battery. or BIOS errors. Usually when IBMs go to Basic (which is in Rom) it's because it's not recognizing any storage device. It could be a dead FDD or damaged disk, which would explain why the reference disk won't work. I've used PS/2s with bad batteries and they function but you have to use the reference disk each time when you start up.

Lawrence

 

[Terry Yager]

One of the codes is for dead battery, and the other is system time & date not set. The Model 70 came with an ESDI drive, and proprietary connection. You can however install a SCSI or IDE drive, if you have a suitable MCA adaptor (and a roll of duct-tape).

--T

 

[Micom 2000]

Technically the HDs in the model 70 are "pretend" ESDIs and normal ESDIs won't work. I've attached a file in which the MCA Guru Peter Wendt describes why.

If you can't get a HD for it you might get an MCA SCSI card and use SCSI drives.

Lawrence

 

[tgunner]

Alright, I have two floppy drives, and each of them work, so the problem is definately the Hard Drive. Now, the decision, do I buy an MCA SCSI adapter, and use a spare 250 MB drive, or try to find an original IBM replacement. The IBM replacement would make the machine more original, but, that drive would still be 16 years old, as old as me! A drive that old is probably on its last leg anyway. The SCSI would allow for a larger drive, and easy access to replacement drives if it should fail. I found this SCSI adpater:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=8770461955&rd=1&sspagename=STRK:MEWA:IT&rd=1

and this original IBM drive: http://cgi.ebay.com/VERY-RARE-VINTA...ryZ74946QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[Terry Yager]

I'd go for the SCSI, for the same reasons you point out. Just make sure the host adaptor is compatible with your system. It looks like a 32-bit card, IIRC, but I don't recall if the Model 70 has 32-bit slots or not.

--T

 

[tgunner]

Yeah, my 70 does have 32 bit slots. Is that a good card? It appears to be from IBM, most likely from a RISC/6000. I've seen Adaptec's come up in the past, but very rarely. Will DOS and window's 3.11 recognize the IBM card? Or, more importantly, will the computer see it without much trouble?

 

[Terry Yager]

You'll have to find the reference disk (or whatever they call it) for that card, but the good news is that they ain't usually too hard to find. Google should turn up something.

--T

 

[tgunner]

A seperate Referance Disk? I already have the referance disk for the Model 70.

 

[Terry Yager]

Each device jacked-into the MCA bus requires it's own drivers, called ADF (AdaptorDescriptorFile), which is seperate from the OS itself. Here is a good place to look for more info (Peter Wendt's page is also a great source):

http://www.gtweb.net/faq.html

--T

 

[tgunner]

His site is nice, except all of the links I need are bad. Apparently, IBM no longer has these files on their ftp, or the address was changed. Still looking for an adapter file for that card though. Found this site: http://www.mcamafia.de/mcapage0/adflist5.htm

 

[USSEnterprise]

I would assume that when IBM transferred their PC line to Lenovo, they would have dropped support for the older computers. But then, Compaq still supports the original portable

 

[Terry Yager]

I dunno, the MCA Mafia site above is the definitive source for MCA info, etc.

--T