[vcf-midatlantic] cranky 5150 - first test results

william degnan billdegnan at gmail.com
Sun Nov 6 12:38:31 EST 2016


this is good, after you turn off the floppy controller switches (your card
may be bad anyway), you probably have a base 256K machine OK.  You then
should switch back in with 64K or 128K tincrements until you find the bad
bank.  Or the entire RAM card is bad, if you can't add another bit past
256K.  Then you can deal with the drive controller and RAM cards, check
caps, etc.  Your ROMS are probably ok is my guess.
b

On Sun, Nov 6, 2016 at 12:13 PM, Steven Michelsen via vcf-midatlantic <
vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:

> Bill,
>
> Before I got you email just now I wrote this:
>
> Realizing that block SW2 was still set to 640k (to account for the ram
> card) I set SW2 from 10110 to 10011, which represents 256k in place.
>
> Turning on the PC resulted in a 601 code (only), then booted to Basic.
>
>
>
> As you suggest, I will look for loose ROMs
>
> I see that the 601 code refers to the floppy controller, so my response
> there is "yes I know, thank you".
>
> Are you suggesting that the next step would be that I physically pull all
> the socketed RAM, leaving just the 64k soldered on (at least to start)?
>
>
>
>
> -----Original Message-----
> From: vcf-midatlantic [mailto:vcf-midatlantic-bounces at lists.
> vintagecomputerfederation.org] On Behalf Of william degnan via
> vcf-midatlantic
> Sent: Sunday, November 06, 2016 12:09 PM
> To: vcf-midatlantic <vcf-midatlantic at lists.vintagecomputerfederation.org>
> Cc: william degnan <billdegnan at gmail.com>
> Subject: Re: [vcf-midatlantic] cranky 5150 - first test results
>
> You have a short in the motherboard, the roms are loose, stuff like that.
> Reduce to minimum RAM by removing from my all except what you need.
> Verify jumpers, if you remove drive controller you have to change jumpers
> to no drives setting.
>
> Bill Degnan
> twitter: billdeg
> vintagecomputer.net
> On Nov 6, 2016 11:25 AM, "Steven Michelsen via vcf-midatlantic" <
> vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:
>
> > FYI my mobo is a 64k-256k board, and the PC serial # is 11483445150.
> >
> >
> > OK I did the test as outlined below:
> >
> > - I pulled the ram card and floppy controller card, leaving only the
> > video card.
> > - I changed switch 3 and 4 on block SW1 to ON, for "bank 0 only"
> >
> > I did the test twice, and got different results:
> >
> > TRY #1:
> > Got a "4090" code, and the PC produced long beeps that did not stop.
> >
> > TRY #2
> > Got the following codes, AND THEN the PC booted to Basic.
> >
> > 4098  201
> > 601
> >
> > What do you make of all this?  And, why would the same test yield
> > different results?
> >
> > Thanks much,
> > Steve
> >
> > -----Original Message-----
> > From: vcf-midatlantic [mailto:vcf-midatlantic-bounces at lists.
> > vintagecomputerfederation.org] On Behalf Of william degnan via
> > vcf-midatlantic
> > Sent: Sunday, November 06, 2016 6:32 AM
> > To: vcf-midatlantic
> > <vcf-midatlantic at lists.vintagecomputerfederation.org>
> > Cc: william degnan <billdegnan at gmail.com>
> > Subject: Re: [vcf-midatlantic] cranky 5150 - PART 2
> >
> > Set the MOBO to minimum RAM, remove all but video controller report
> > result
> >
> > Bill Degnan
> > twitter: billdeg
> > vintagecomputer.net
> > On Nov 5, 2016 5:05 PM, "Steven Michelsen via vcf-midatlantic" <
> > vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:
> >
> > > Uh oh.  After writing the post below I read the appropriate
> > > minuszerodegrees page, that suggested among other things, "Faulty
> > > motherboard - bad solder joint on keyboard connector".  So I took a
> > > look - here's what I found.  Not promising.  But fixable!  Does this
> > > look like the culprit?  But what about the memory errors?
> > >
> > >
> > >
> > > https://www.youtube.com/watch?v=3A9uULoyJgk
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > From: Steven Michelsen [mailto:stevenm at optonline.net]
> > > Sent: Saturday, November 05, 2016 4:55 PM
> > > To: 'vcf-midatlantic'
> > > <vcf-midatlantic at lists.vintagecomputerfederation.org
> > > >
> > > Subject: cranky 5150
> > >
> > >
> > >
> > > I thought for once I could get a new IBM 5150 and NOT have to come
> > > crawling to the group for advice, but noooo..
> > >
> > >
> > >
> > > Just got an ebay 5150.  I couldn't resist - it was relatively local,
> > > and included a 5151 monitor (but no keyboard), for a decent price.
> > > I have a keyboard, so no worries.  Took the top off to peek inside
> > > to confirm everything was seated, etc.  I started it (with the top
> > > off) and got a keyboard error (301).  I discovered that my keyboard
> > > was set on AT instead of XT.  Flipped that switch and viola, the
> > > 5150 booted with a Dos 2.11 disk.
> > > Poked around the disk, ran a Basic file that happened to be on it,
> > > tested the "B" drive, formatted a disk - it's all good.  I even
> > > booted a few times with no issue.
> > >
> > >
> > >
> > > I put the lid back on and started it again.  This time I get this.
> > >
> > >
> > >
> > > 40FF
> > >
> > >
> > >
> > > . and the PC is beeping away, long beeps that do not stop!
> > >
> > >
> > >
> > > I restart again and get this.
> > >
> > >
> > >
> > > 40FF
> > >
> > > 201 301
> > >
> > >
> > >
> > > This time there's no beeping, it just displays the msg.  The disk
> > > drive was read from briefly, then nothing.
> > >
> > >
> > >
> > > I pull out what appears to be a memory expansion card.  Here
> > > <https://dl.dropboxusercontent.com/u/65762317/forums/IBM_5150_RAM_
> > > board.jpg>
> > > 's a picture of it.  I started it without the card and get this.
> > >
> > >
> > >
> > > 40D0
> > >
> > >
> > >
> > > I took another look at that RAM card and found THIS on the back
> > > <https://dl.dropboxusercontent.com/u/65762317/forums/5150_bug.jpg> !
> > > My PC had a bug.  Anyway, cleaning that up didn't help.  I replaced
> > > the card, started it and got yet another, different 40xx error.
> > >
> > >
> > >
> > > OK, where do I go from here?  The darn thing worked at one point
> > > today; why not all the time?  I have looked for unseated chips,
> > > cards and cables, as least as far as I could without pulling a
> > > floppy drive, and found that everything is secure.
> > >
> > >
> > >
> > > Thanks as always,
> > >
> > > Steve
> > >
> > >
> >
> >
>
>



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