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bettablue
April 19th, 2012, 06:29 PM
In rebuilding the IBM 5161 expansion unit, I ran into an issue where the wider MFM cable that can connect to 2 drives was too short. I was sondering if there is such a thing as a longer MFM cable, or an extension that I can add onto the one end with the twist for adding in the 2nd MFM drive side by side. (Sorry, I don't know any better way to explain it). When installing the 2nd drive, I had to be very creative in how I ran the cable over to the end of the controller. In the end, I had to run all of the MFM cables from the 2nd drive completely underneath the first drive. The smaller of the cables was OK, it was only the larger cable that gave me any real trouble.

So, is there a cable that can handle both a longer space between the controller and the first drive, AND a longer space between the 1st and 2nd drive? Or is ther an extension I can use between the 2 drives to gain the extra length I need?

Also, I'm still looking for another MFM hard disk to complete outfitting the expansion unit. Please PM me if you have a drive.

Thanks much.

twolazy
April 19th, 2012, 06:33 PM
I remember years ago having a similar issue with a different system (trs-80 coco external drives). I ended up just pulling off the ends carefully, and buying a spool of ribbon cable at radio shack. Problem is I don't think radio shack sells ribbon cable anymore. :S I still have some, if you can't locate any. At least 30-40 feet.

You will most likely have to make your own cable. Also I have a drive if your interested, st-225, but its missing the bezel. Not sure its working condition, been sitting on a shelf for years... It was parked w/ sit.com before being pulled though. :thumbsup:

SpidersWeb
April 19th, 2012, 06:51 PM
I was about to say "just fit a single ST225", but if I had 5161 I'd want that badboy loaded out too!

ST-225's are good drives.
For 20Mb drives tho you'd want to check your controller has Type 2 hard drive support, and for any early drive be sure it was parked before being sent.

Another cheeky resource for connectors and cable is old floppy cables - you just need to remove the A-drive-twist and make a new C-drive-twist like the current cable has (or be lazy and set C drive to DS0 instead of DS1, which is what I do). If only I could find the same for 20 pin data connectors :(

bettablue
April 19th, 2012, 10:53 PM
Thanks for the quick responses. I am in the works to possibly buy a drive and controller combo at a very good price. Someone sent me a PM telling me what they have, so I'm looking at going that rout.

As far as the cable is concerned. It almost sounds like it's a very simple thing to do to remanufacture these cables. Spider, and TwoLazy; I don't know what you mean by "be lazy and set C drive to Ds0 etc. However, if I send you an extra cable I have, do you think you could put together a cable for me? I kind of think I understand what you mean, but I do want to make sure everything is set up properly in the 5161 expansion unit. If all it takes is to remove the connnectors and reattach them after making the "twist", I'm sure I could do that. In theory, I guess you could make a drive ribbon and any desired length, am I correct?

I just had a small problem though. My wife did some housekeeping and she tossed out an entire box of ribbon cables. I can probably make the ones I have work OK, but If there was some way I could just purchase a cable with the length between drives extended by about 4" and the length from the contoller to the first drive also extendsed by 4 ". That would give me a total of 8 inches of expansion on that cable and with that I could run it pretty much anywhere I needed. Let me know if this is something we can set up.

Thanks again.

Stone
April 20th, 2012, 05:01 AM
Another cheeky resource for connectors and cable is old floppy cables - you just need to remove the A-drive-twist and make a new C-drive-twist like the current cable has (or be lazy and set C drive to DS0 instead of DS1, which is what I do). If only I could find the same for 20 pin data connectors :(Not quite... that configuration will only work with a ribbon cable with no twist at all. So, he'll still need to tear the ribbon apart to remove the (floppy) twist.

Stone
April 20th, 2012, 05:08 AM
BB, I have something very unusual that would no doubt solve your problem with very little effort. This is something I picked up a long time ago when I was running external floppies and hard drives from my 286. Not external floppies and HDs, mind you, but normal, internal drives attached to another power supply, outside the box.

I obviously needed longer than normal cables to get these drives to my controller(s) located inside the box so here's what I did. I picked up a couple of double-sided PCB edge card connectors. This allowed me to connect two ribbon cables together to extend them. It worked like a charm and I used that setup for many years with no problems.

If you're interested I'll dig this little device out of wherever it's hiding. :smile:

Here's a pic... 8589

Stone
April 20th, 2012, 05:54 AM
I can probably make the ones I have work OK, but If there was some way I could just purchase a cable with the length between drives extended by about 4" and the length from the contoller to the first drive also extendsed by 4 ". That would give me a total of 8 inches of expansion on that cable and with that I could run it pretty much anywhere I needed. Let me know if this is something we can set up.Here's another option. How long is the cable you have from the controller to the first drive connector and how long is it between the two drive connectors? I have some NOS 36" floppy ribbon cables and I could convert one to match your needs -- once you confirm the current measurements you're working with.

barryp
April 20th, 2012, 06:33 AM
I have saved every cable over the years and have a LOT, including 16-pin, 20-pin, 34-pin, 40-pin, 50 pin, ribbon cables, Centronics, DB-9, DB-25 and some others. Everybody should become expert at removing connectors and reinstalling them as needed.

bettablue
April 20th, 2012, 08:10 AM
Stone: I'll take you up on that. Just for S&G, do you happen to have an edge connector for the smaller MFM cable too? If possible, I want to lengthen both cables so there is no stress anywhere in the cabling or on the controller card or drives. Hmm. Did the expansion unit come with a special, longer cable set? Just let me know what I owe you for the cable you're making and the edge connector for the smaller cable if you have one. I'll send payment through Paypal.

I also have someone else putting together a cable for me too. But I want to keep both options available. Besides, if a cable is too long, I can work with that. When a cable is too short that causes problems.

The primary cable that needs to be lengthened is the larger of the two. So, IF you can add about 4 inches to each section, one to allow more room to rout to the first drive, then the other section to allow connecg the same cable to the 2nd hard drive. We're talking about 8 inches total, if possible.

Thanks again.


Here's another option. How long is the cable you have from the controller to the first drive connector and how long is it between the two drive connectors? I have some NOS 36" floppy ribbon cables and I could convert one to match your needs -- once you confirm the current measurements you're working with.

bettablue
April 20th, 2012, 08:14 AM
I have saved every cable over the years and have a LOT, including 16-pin, 20-pin, 34-pin, 40-pin, 50 pin, ribbon cables, Centronics, DB-9, DB-25 and some others. Everybody should become expert at removing connectors and reinstalling them as needed.

I agree. That's why I'm going to look for an old ribbon cable I can play around with. As I see it, that is something I can learn. The bad part for me is that I am a polio survivor and only have one arm that works. So manipulating smaller things like that is much more difficult for me. I appreciate the assistance of those two gentlemen immensly.

Chuck(G)
April 20th, 2012, 08:21 AM
I keep a few spools of ribbon cable around--that way, I can make any length of cable that suits me, including some 6 and 8 foot cables for tape drives. Having 50 and 34 conductor bulk ribbon is a good way to go--with some searching, sometimes you can find it as surplus. I prefer Spectra-strip type--I don't have to count conductors when I'm looking to single out one.

Stone
April 20th, 2012, 08:24 AM
The primary cable that needs to be lengthened is the larger of the two. So, IF you can add about 4 inches to each section, one to allow more room to rout to the first drive, then the other section to allow connecg the same cable to the 2nd hard drive. We're talking about 8 inches total, if possible.Yes, but the reason I asked for your exact measurements before is that floppy/hard ribbons come in many sizes and simce I'm not there I don't want to send you something that might not fit. So, take the measurements and then I can be sure of what I'm doing. :-) You can either give me the two measurements I asked for above or the total length and the length between the two drive connectors, either way. Just make sure you specify what measurements you're giving me. You don't even need to be too precise. The nearest half inch will suffice.

bettablue
April 20th, 2012, 08:28 AM
In addition to the cable issues we have been discussing in this thread, I have an opportunity to purchase a Control Data 20mb Full-height + Paired controller from a member who replied to this thread. The price is perfect for me, but is this combination compatible with my miniscribe 2012 11 Meg hard drive? Or is the Xebec controller compatible with the Control Data 20 Meg drive? I'm including information on the Xebec controller that Chuck supplied in another of my threads.

From Chuck (G)

"very close to "Variation #2". It's assy. 104836-Rev C-04-06. It has the option jumpers installed (4 of them) and a 28-pin socket for a 2764 BIOS ROM. Currently, there's an SMS/OMTI 5520 ROM installed (giving 16 drive types)"

If either combination will work, I'm going to purchase the drive and controller.

Thanks again everyone.

bettablue
April 20th, 2012, 08:44 AM
Gotcha. The reason I gave you the measurements I did was because the system is currently assembled. However, from what I can tell, the connection from the controller to the first drive is 9 1/2 inches, and the distance between the two drive connectors is 10 inches, but there will need to be additional room for the cable to be routed and bent into place. Because of the way ribbon cables have to be kind of folded into place to change direction, adding let's say, another 2 to 2.5 inches between the drives will be fantastic. That way I can run the ribbon under the drives and up to their connectors.

Since you're doing that. I'll tell the other guy to hold off.

Thanks again stone.


Yes, but the reason I asked for your exact measurements before is that floppy/hard ribbons come in many sizes and simce I'm not there I don't want to send you something that might not fit. So, take the measurements and then I can be sure of what I'm doing. :-) You can either give me the two measurements I asked for above or the total length and the length between the two drive connectors, either way. Just make sure you specify what measurements you're giving me. You don't even need to be too precise. The nearest half inch will suffice.

Stone
April 20th, 2012, 09:43 AM
I'll make it roughly 20" - 21" from controller to the first drive and 15" - 16" between the two drives.

That brings up one more question. You're going to use this on the Xebec controller, right? IIRC, that has a 34 pin header to connect to the ribbon cable, right? Not some 34 connector card edge like on the old floppy controllers, right? Just wanna be sure. :smile:

BTW, I don't have that data cable (20 connector) double card edge adapter you asked about but I do have some longer data cables. How long is yours and how long does it need to be?

Dwight Elvey
April 20th, 2012, 03:56 PM
Hi
A 90 degree bend add the width of the cable
to the length.
Run a string from connector to bend to
connector.
That should get it right
Dwight

modem7
April 20th, 2012, 04:31 PM
That brings up one more question. You're going to use this on the Xebec controller, right? IIRC, that has a 34 pin header to connect to the ribbon cable, right? Not some 34 connector card edge like on the old floppy controllers, right? Just wanna be sure.
Yes. Photos at http://www.minuszerodegrees.net/ibm_xebec/ibm_xebec.htm

modem7
April 20th, 2012, 04:49 PM
In addition to the cable issues we have been discussing in this thread, I have an opportunity to purchase a Control Data 20mb Full-height + Paired controller from a member who replied to this thread. The price is perfect for me, but is this combination compatible with my miniscribe 2012 11 Meg hard drive? Or is the Xebec controller compatible with the Control Data 20 Meg drive?
Take a look at the following link to gain an understanding of how to answer those two questions.
http://www.minuszerodegrees.net/5160/hdd/hdd_question.htm
The link is not comprehensive (e.g. doesn't cover autoconfigure controllers) - its aim is to provide a basic understanding, which should be enough for you to answer the questions.

The Xebec controller Chuck supplied has a "SMS/OMTI 5520 ROM". That ROM will define the drive types. Maybe Chuck can tell you what those types are. Otherwise, SpeedStor software may be able to list the types via its /romlist option (done via A:\>sstor /romlist)

Chuck(G)
April 20th, 2012, 06:08 PM
After I learned that Thomas was getting a Miniscribe, I re-installed the original Xebec ROM.

I believe it has the following 4 selections for each drive:

306/4/17 off-off
612/4/17 off-on
615/4/17 on-off
306/8/17 on-on

At any rate, it's one of the IBM ROMs, so I think that's the one I put in.

You can check by using debug to look at C800:0. You should see:


55 AA 08 EB 35 35 39 58-37 32 39 31 20 28 43 29 U...559X7291 (C)
20 43 4F 50 59 52 49 47-48 54 20 49 42 4D 20 20 COPYRIGHT IBM
43 4F 52 50 2E 2C 31 39-38 32 20 2C 31 39 38 35 CORP.,1982 ,1985
2E 20 31 30 2F 32 38 2F-38 35 2B C0 8E D8 FA A1 . 10/28/85+.....

If you don't see that, let me know what you do see and I'll look it up. Too many ROMs, too little time.

bettablue
April 20th, 2012, 06:36 PM
OK, so what am I doing wrong? When I run the Debug command the computer accepts that, but it doesn't accept the address you provided. I tried C800:0 C80:00.0. and multiple other variations, all come up with the same ^error

I would like to try doing this without taking the system down just now. It took me forever to get it set up the last time and my best friend won't be here for another week.


After I learned that Thomas was getting a Miniscribe, I re-installed the original Xebec ROM.

I believe it has the following 4 selections for each drive:

306/4/17 off-off
612/4/17 off-on
615/4/17 on-off
306/8/17 on-on

At any rate, it's one of the IBM ROMs, so I think that's the one I put in.

You can check by using debug to look at C800:0. You should see:


55 AA 08 EB 35 35 39 58-37 32 39 31 20 28 43 29 U...559X7291 (C)
20 43 4F 50 59 52 49 47-48 54 20 49 42 4D 20 20 COPYRIGHT IBM
43 4F 52 50 2E 2C 31 39-38 32 20 2C 31 39 38 35 CORP.,1982 ,1985
2E 20 31 30 2F 32 38 2F-38 35 2B C0 8E D8 FA A1 . 10/28/85+.....

If you don't see that, let me know what you do see and I'll look it up. Too many ROMs, too little time.

Chuck(G)
April 20th, 2012, 06:56 PM
Did you try:


DC800:0

"D" for "dump", "Q" for quit, and so forth as detailed in the MS-DOS reference.

I should add that, depending on the BIOS used for the Xebec, you can either get two different capacity drives on the controller or two of the same capacity drive. In other words, you've got 4 jumpers. You can divide them as 2 for one drive and 2 for the other drive (4 possibilities for each) or 4 for both drives (16 possibilities, but only for both drives).

Xebec BIOSes, depending on their vintage, can do one or the other. That's why I want to see what's at C800:0...

bettablue
April 21st, 2012, 05:34 AM
Below is a thread through PM on this subject. In it k2 and I discuss the purchase of a Control Data 20mb Full-height hard disk drive and WD controller. The WD is really the controller I wanted to begin with, but the Xebec was what I could afford. k2 is setting up the controller as we speak.

Along with this purchase, and that of the cable stone is working up for me, the expansion unit will be in great shape and will have enough hard drive space to do what I want quite easilly.

Don't worry stone, there won't be any changes to the cable length and we're still using the pin connector and not the edge conector. So when everything arrives, it will be ready to rock and roll.

There really is only one more question to ask regarding the new setup, and this would primarilly be for Chuck (G) Once I have the WS controller and the Control Data hard disk drive installed, will I HAVE to do a low level format on the Miniscribe drive? Or will it work "out of the box" so to speak? Not that it matters all that much, but since the Miniscribe is already working and most of the DOS configurations are already in place, I could save some time.

What are your thoughts?


Originally Posted by k2x4b524[

That all i needed to know, thanks for the clarification. I'll setup the drive and controller on my test bed over the weekend, give it some spinrite and then it will be ready. But remember, check with chuck to be sure *Far more knowledgeable on these things than i* You may want to low level format the miniscribe to pair it to the WD controller aswell. I'd use the WD it's FAR easier to work with than the Xebec controller..

[QUOTE=bettablue]I will only go for the extra drive IF an only if both can be run from the same controller. It doesn't matter which controller as long as both drives will connect to it, and the drives both run.

I would prefer the WD, but I see in the thread that the Xebec may be capable of running the drive you have. I wasn't able to run a successful debug command though.


Originally Posted by k2x4b524[

Are you planning on using BOTH controllers? Or running both drives off of the Xebec, or the WD? If your planning on using the Xebec, i believe that it will support the 20mb fine, but will have to be paired, and vice versa with the 10mb, but that shouldn't really be a problem, the WD is pretty quick on the format. If you send me the model # of the Miniscribe, i can look up the specs on the drive, as well as how to setup it up for the dual configuration. One of the books i have has ALL the older drives specs in it, saved my ass on numerous occasions. I DO know you have to tell the WD controller the dimensions of the drive, you might want to check, but i think that is common of the controllers of the time, besides, the WD supports a better interleave i believe, so a low level couldn't hurt *may even be required* Also, would you like me to include something like Norton Utilities and XTree Gold on the drive? Anything special you may require?

Originally Posted by bettablue

For what I have planned for this system, 20 Megs for the 2nd drive will be fine, as long as the 10 Meg Miniscribe can be used for booting DOS and all of the DOS commands and programs. This will be a perfect setup.

I don't believe I'll have to format the Miniscribe. When Chuck set up the Xebec controller, the system booted right into DOS on the first try. So I'll want to try again doing the same thing. However, if you give me the instructions for completing the setup, after everything arrives, I'll be fine.

You have no idea how much I appreciate you doing this for me.


Originally Posted by k2x4b524[

That will work famously, I'll see if i can get a dummy setup using my miniscribe 40mb as master and the cdc as slave *so to speak*. If that doesn't work out the way we'd like, i'll give detailed instructions on setting it up as the second drive. But i don't see how it wouldn't, but you may have to low-level your 10mb to pair it to the WD controller once you get it. I believe i have some rather long floppy drive cables that i can turn into straight through for the controller, if that's the case the CDC will be set to drive 1. or 2, *The second drive* in the setup, you'd just have to make sure your 10mb if it's strapped to be drive 0, or 1, *The first drive*. Will 20mb be enough?

Originally Posted by bettablue

Fantastic. I was actually hoping to get a WD controller because they seem to be compatible with more drives than most among other things. OK, here's the config I would like. I want the Miniscribe to be the primary hard disk drive, so I won't have to change anything on it when the other drive and controller arrive. That also means your drive should be left empty. I hope you can at least make sure it's ready to install and accept data as the 2nd drive. I'll be instlling several productivity and business apps on it. Later of course, I'll be adding directories as I need them, but this configuration will be perfect for my setup.

I can make a money order for you, no problem. So, can you get the WD card set up that way? That way, I'll keep my current install and configurations, and you won't have to install DOS, but rather leave the drive formatted, empty, and in park. I can easilly take it from there.

Please let me know if that will work for you.

Thomas.

Chuck(G)
April 21st, 2012, 07:57 AM
There really is only one more question to ask regarding the new setup, and this would primarilly be for Chuck (G) Once I have the WS controller and the Control Data hard disk drive installed, will I HAVE to do a low level format on the Miniscribe drive? Or will it work "out of the box" so to speak? Not that it matters all that much, but since the Miniscribe is already working and most of the DOS configurations are already in place, I could save some time.

Most likely you'll have to reformat (low-level) the Miniscribe. As far as I know, Xebec's formatting is not compatible with WD's. So if you want to carry the Miniscribe over, you'll have to save the data from it.

bettablue
April 21st, 2012, 08:02 AM
Most likely you'll have to reformat (low-level) the Miniscribe. As far as I know, Xebec's formatting is not compatible with WD's. So if you want to carry the Miniscribe over, you'll have to save the data from it.

That makes sense. So, a backup is in order. Thanks everyone. This thread turned out to be a great help.

bettablue
April 23rd, 2012, 08:03 PM
When I ran debug, I got a bunch of garbage on the right side. Nothing made any sense. I was wondering if I was doinng something wrong. The main area looks simliar to your table, but the table I get is completely different.




Did you try:


DC800:0

"D" for "dump", "Q" for quit, and so forth as detailed in the MS-DOS reference.

I should add that, depending on the BIOS used for the Xebec, you can either get two different capacity drives on the controller or two of the same capacity drive. In other words, you've got 4 jumpers. You can divide them as 2 for one drive and 2 for the other drive (4 possibilities for each) or 4 for both drives (16 possibilities, but only for both drives).

Xebec BIOSes, depending on their vintage, can do one or the other. That's why I want to see what's at C800:0...

Chuck(G)
April 23rd, 2012, 08:15 PM
Without knowing what you enter or see, it's hard to say what you've got!

bettablue
April 24th, 2012, 08:45 AM
Sorry for the confusion. I don't have a good DOS manual to refer to for the debug command. But I finally found what I hope you want for this. Hope this helps. What I also noticed is that running the "D" command in Debug will give continually different results. The only way to get the same inital result is to end the debug and start it again.

107E:0100 59 5B C3 B9 0B 00 BE 5D - 00 AC 3C 3F 75 02 E2 F9 Y [C9..>].,<?u.by
017E:0710 83 F9 00 75 31 BA 0C 3B - E8 99 0C BE 80 00 8B D6 .Y.u1:.:h..>…0
017E:0720 CY 02 78 00 B8 0A 0C CD - 21 AD 0A E4 74 E7 E8 22 G,x.8..M!-.dtgh"
107E:0130 F1 E8 7E 01 3A 06 B9 3D - 75 01 C3 3A 06 B8 3D 9C gh".:.9=u.C:.8=
017E:0740 E8 03 F1 9D 75 CF B4 13 - BA 5C 00 CD 21 FE C0 74 h.g.u04.:\.M!~@t
017E:0750 04 E8 21 F0 C3 B4 1A BA - 5C 00 CD 21 B4 11 CD 21 .h!pC4.:\M!4.M!
017E:0760 50 E8 11 F0 58 BA 18 38 - FE C0 74 3D BA 3D 38 E9 Ph.pX:.8~@t=:=8i
017E:0770 9B F3 E8 94 00 72 12 8E - 1E 91 42 75 06 80 0E ED .sh..r….Bu…m



After I learned that Thomas was getting a Miniscribe, I re-installed the original Xebec ROM.

I believe it has the following 4 selections for each drive:

306/4/17 off-off
612/4/17 off-on
615/4/17 on-off
306/8/17 on-on

At any rate, it's one of the IBM ROMs, so I think that's the one I put in.

You can check by using debug to look at C800:0. You should see:


55 AA 08 EB 35 35 39 58-37 32 39 31 20 28 43 29 U...559X7291 (C)
20 43 4F 50 59 52 49 47-48 54 20 49 42 4D 20 20 COPYRIGHT IBM
43 4F 52 50 2E 2C 31 39-38 32 20 2C 31 39 38 35 CORP.,1982 ,1985
2E 20 31 30 2F 32 38 2F-38 35 2B C0 8E D8 FA A1 . 10/28/85+.....

If you don't see that, let me know what you do see and I'll look it up. Too many ROMs, too little time.

bettablue
April 24th, 2012, 10:25 AM
Chuck, that one gave me a Copywrite IBM 1982. on the right side.

Is there anything else I need to do? As I mentioned I don't have a good copy of a DOS reference manual. So, do you still need the entire grid?


Did you try:


DC800:0

"D" for "dump", "Q" for quit, and so forth as detailed in the MS-DOS reference.

I should add that, depending on the BIOS used for the Xebec, you can either get two different capacity drives on the controller or two of the same capacity drive. In other words, you've got 4 jumpers. You can divide them as 2 for one drive and 2 for the other drive (4 possibilities for each) or 4 for both drives (16 possibilities, but only for both drives).

Xebec BIOSes, depending on their vintage, can do one or the other. That's why I want to see what's at C800:0...

MikeS
April 24th, 2012, 10:34 AM
... As I mentioned I don't have a good copy of a DOS reference manual... Lots of info and even tutorials on the web...

bettablue
April 24th, 2012, 12:14 PM
Yeah, that's where I found the info on Debug. I just hope what I got is what Chuck is looking for. I also just ordered a DOS 3.3 manual through E-Bay too, so hopefully I 'll be able to learn a lot more about DOS as I go through that when it arrives.

As an aside, if I can only be sure of the hard drive sale I' ve been working on trying to complete, the expansion unit will be in fantastic shape with only a few minor things to go. I was making a deal with k2x4b524 but he's probably busy with work and family during the week. He's the one with the Control Data hard disk drive and Western Digital controller. So hopefully when we finaly do get to chat, I'll finalize that deal and I can concentrate on getting the last couple ISA cards I want to complete oufitting the expansion.

I can't believe the system is finally almost done.

Next I'm going to turn my attention to the XT computer I got from Hargle last year. We got that one for my wife as a birthday gift. She loved it, and still does. Hargle was good enough to configure it with a 30 Meg hard disk drive, and mono graphics adapter, but I'm going to trade out some of the parts it it with things I removed from my 5150 as I upgraded. I think it's also running an AST six Pack, but it's also missing 64 Kb of RAM. I think I narroed it down to one of the chips on the memory expansion, so I'm going to reconfigure the AST to "forget" the RAM so I can use the 384KB RAM upgrade. I'm also going to be looking for an 8 bit sound card for both the 5161 expansion unit and the 5160 XT. Who knows where this project will take me, I won't be taking the XT anywhere near what I did for the PC though. After that, I want to take on a rebuild of an IBM 5170 AT system.

Then my collection of IBM computers will be complete. I'm not interested in PC jr. or any of the later PCs simply because once they got past the 5170, it seems like everything was already starting to get redundant across the brands.


Lots of info and even tutorials on the web...

modem7
April 24th, 2012, 02:58 PM
Chuck, that one gave me a Copywrite IBM 1982. on the right side.
Refer to http://www.minuszerodegrees.net/ibm_xebec/ibm_xebec.htm

Of the two items below, Chuck was expecting you to have item 2.
But it sounds like you have the ROM described in item 1.
Is that the case?

1. IBM ROM used in IBM/Xebec controller variation #1 and #2:
* Stamped "5000059" or "6359121"
* At start, contains text of "5000059 (C)COPYRIGHT IBM 1982"

2. IBM ROM used in IBM/Xebec controller variation #3:
* Stamped "62X0822"
* At start, contains text of "559X7291 (C) COPYRIGHT IBM CORP.,1982 ,1985. 10/28/85"

bettablue
April 24th, 2012, 03:05 PM
Yes it is. Chuck loaded the ROM to work with the Miniscribe disk drive.



Refer to http://www.minuszerodegrees.net/ibm_xebec/ibm_xebec.htm

Of the two items below, Chuck was expecting you to have item 2.
But it sounds like you have the ROM described in item 1.
Is that the case?

1. IBM ROM used in IBM/Xebec controller variation #1 and #2:
* Stamped "5000059" or "6359121"
* At start, contains text of "5000059 (C)COPYRIGHT IBM 1982"

2. IBM ROM used in IBM/Xebec controller variation #3:
* Stamped "62X0822"
* At start, contains text of "559X7291 (C) COPYRIGHT IBM CORP.,1982 ,1985. 10/28/85"

modem7
April 24th, 2012, 03:24 PM
Yes it is. Chuck loaded the ROM to work with the Miniscribe disk drive.
The question then became which IBM ROM was fitted.

So you have either the 5000059 or 6359121 stamped ROM (same contents). Per the web page I quoted in my previous post, that ROM supports only one drive, one with: cylinders = 300, heads = 4, WPC = 0, Step Rate = 70 uS.
An example of such a drive is the Seagate ST-412.

bettablue
April 24th, 2012, 03:48 PM
Yes, That's what we figured. That is why I am replacing it with a WD controller that is being configured for me right now. k2 is getting hid Control Data drive ready to go as well. So by the end of the week, we should have the deal closed. I also have the cables coming in from stone. He set my up with a much longer set to accomodate the extra length required for the 2nd drive.

Modem7, I thank you again. You are always helpful. I apreciate all you've done for me.



The question then became which IBM ROM was fitted.

So you have either the 5000059 or 6359121 stamped ROM (same contents). Per the web page I quoted in my previous post, that ROM supports only one drive, one with: cylinders = 300, heads = 4, WPC = 0, Step Rate = 70 uS.
An example of such a drive is the Seagate ST-412.

Chuck(G)
April 24th, 2012, 03:51 PM
Not so--if you have the Xebec card fitted with the option jumpers (just blank solder pads on the IBM version, but Thomas has the Xebec card), you get 4 drive types. Look at the table at offset 3e7 in 6359121, for example. That IBM didn't want to spend 25 cents to add the jumpers must have been to lock to buyers into IBM's drives--I can't explain it otherwise.

Similarly, the Xebec Mitsubishi ROM can accommodate 8 different drive types, but I think both drives have to be the same.

The Zenith Z-100 hard disk option also used a Xebec controller, but I haven't found the BIOS ROM for that one.

No matter, you can tailor ROMs to anything you'd like to support. I shipped the Xebec with a 28C64 EEPROM for just that reason. If you can program an EEPROM, you can make the Xebec do whatever you need.

modem7
April 24th, 2012, 04:44 PM
Thomas. In case you are unable to put all the relevant posts together:

* You have a Xebec card, not what some may refer to as an IBM/Xebec card (made for IBM by Xebec).

* Presently, the ROM contents support the 4 drive types shown at http://www.minuszerodegrees.net/ibm_xebec/variation_2_switch.htm

* There are switches/jumpers on the card to control which of the 4 types is used, although the switches/jumpers won't necessarily match with what is shown at the web page I pointed to earlier.

* Because Chuck has thoughtfully fitted an EEPROM instead of a 'vanilla' ROM, you may be in a position (with guidance) to change the 4 drive types supported.

bettablue
April 24th, 2012, 05:21 PM
Thanks for clearing that up for me. I did think it was the IBM Xebec at first.

So I have to find out if the Control Data fits the drive types in the table. I'll look into that. If not, again, no big deal. A WD card is coming with the drive, and will be preconfigured to operate with the miniscribe drive as drive "C" . Also, once everyting is installed, I'll be completing a low level format, FDISK and final format prior to the fresh install of DOS 3.3 on the Miniscribe drive. I found the software packets for the AST Six-Pack plus, and the 8/16 LAN Adapter. So I'll get those installed and configured too.

I'm not tied to one controller over the other as long as it works. Because I know how stable DOS really is, it will probably stay set up that wy for a long time. That's one of the things I like best about DOS based systems. They're almost bullet proof.

I'm just glad to have this build almost done.


Thomas. In case you are unable to put all the relevant posts together:

* You have a Xebec card, not what some may refer to as an IBM/Xebec card (made for IBM by Xebec).

* Presently, the ROM contents support the 4 drive types shown at http://www.minuszerodegrees.net/ibm_xebec/variation_2_switch.htm

* There are switches/jumpers on the card to control which of the 4 types is used, although the switches/jumpers won't necessarily match with what is shown at the web page I pointed to earlier.

* Because Chuck has thoughtfully fitted an EEPROM instead of a 'vanilla' ROM, you may be in a position (with guidance) to change the 4 drive types supported.

modem7
April 24th, 2012, 05:41 PM
So I have to find out if the Control Data fits the drive types in the table. I'll look into that. If not, again, no big deal.
Per the web page I pointed to at post #18, if there is no direct match (ignore WPC if you have to), then you may be able to run the drive at reduced capactity.
Alternately, you may be in a position to go down the path of altering the card's EEPROM contents to match the drive.

bettablue
April 24th, 2012, 05:53 PM
Per the web page I pointed to at post #18, if there is no direct match (ignore WPC if you have to), then you may be able to run the drive at reduced capactity.
Alternately, you may be in a position to go down the path of altering the card's EEPROM contents to match the drive.

In either case, whether or not I use the Xebec, or the WD, one of the two cards will work fine. I can try both to see what happens, abd in the end, one will work just fine, possibly both. Without the drive to verify them against, all we're doing is spinning in circles. Don't get me wrong, I know where both of you are coming from. I can afford to be patient for once, and I intend to. If I stay with the Xebec, great, if the Xebec doesn't work as I expect it to, then the WD is the way to go. I'm not going to make a decision until I try both cards. And, yes, the Xebec will be the first one to try simply because it's already working with the Miniscribe.

Don't worry though my friends. I'm not going to just jump into one direction or the other until I have tried things in a logical manner.

Stone
April 25th, 2012, 03:20 AM
I also just ordered a DOS 3.3 manual through E-Bay too, so hopefully I 'll be able to learn a lot more about DOS as I go through that when it arrives.In the meantime, here's a DOS program I've had forever and think it's well worth the time to have and look at. It's PC Computing's Best of DOS Help! I got this disk way back when and it's one of the best, free reference materials I've seen. Simple, easy and menu driven.

http://www.filefactory.com/file/1gevqd9adva7/n/BESTODOS_ZIP