View Full Version : IBM 5150a

January 2nd, 2014, 12:25 PM
This is a continuation of the following thread but I thought I'd put it in the proper form since I got it! [Link to old thread] (http://www.vintage-computer.com/vcforum/showthread.php?40385-IBM-5150-on-ebay&p=308112)

The IBM 5150a is pristine but it has a couple of inconsistencies.

1. One floppy drive is marked "IBM" on the front. The first drive has no external markings but an IBM sticker buried in the mechanism.
2. There are some surface scratches on the bottom of the case but they are very light. Otherwise, the case looks 9/10+
3. The AST SixPack Plus isn't fully populated and doesn't have a black bracket like all the other cards.

Tried to power it up but got a 301 error. I was trying to use the only old keyboard I had, an IBM model M (1390120 - Feb 19, 1986) which is almost as eary as they get (except for my Jan 13, 1986 that is earlier but I wouldn't sacrifice). I could type but garbage came up. I also tried a Commodore PC 10-III keyboard but the machine came up REALLY slow (minutes) so I gave up before causing possible damage (and before it tried to finish booting!). I sort of knew both wouldn't work but the Model M is very early and I have read that it just might work with an IBM XT. I gave it a shot but no luck.

I ended up hooked it up to a Commodore 1902a for the CGA graphics as I don't have the IBM 5153 (maybe some day). This worked very well. On a side note, this is used on my Commodore PC10-III.

The IBM 5150a boots up to the DOS 5 set up but I have no keyboard to try anything else. I did purchase a proper model F (83 keys) so I will be able to do something with it when it comes.

Here's a few pics:

I am very happy with this.

January 2nd, 2014, 01:47 PM
I am very happy with this.That is all that really matters. Have fun....................

January 2nd, 2014, 03:43 PM
That is one clean PC, nice catch!

January 2nd, 2014, 04:55 PM
Thanks. Sorry that this thread doesn't have anything to fix to make it interesting :) I just wanted to note for anyone searching that you could use the Commodore 1902a monitor as normal CGA and the IBM Model M keyboard won't work on this ROM version. I will post a thread on my 5140 convertible tomorrow. My screen is messed up and since it's not backlit, I need better light to take a pic :)

Thanks to vwestlife an this video: http://www.youtube.com/watch?v=7YgrLL2Av40 I didn't know you could boot up without a floppy into version 1.0 of Microsoft Basic. And I've been parked at modem7's site for the last few days. Tremendous info there. Thanks modem7 for all that work.

January 3rd, 2014, 12:40 AM
I actually bid on that one myself. She's a beauty!

January 3rd, 2014, 07:08 AM
The 5150 PC (and the XT) uses a different keyboard protocoll than the AT, and not all AT-keyboards are able to support the older protocoll. Of the keyboards that does support both protocolls, some keyboards (for example later Model M Keyboards) will autodetect which protocoll to use while other keyboards may have a mechanical switch that selects the protocoll.