Been a little while since I had time to do a proper update.
First up is a techy update. I launched a collection mission which started at stupid o'clock heading over to Cambridge to pick this thing up.
The lesser spotted IBM sewing machine as one of my family commented.
Which for those not in the know, no is not a sewing machine. This is an IBM PS/2 P70. Which is basically a PS/2 Model 70 crammed into a portable form factor. A machine which usually sits well, well out of my price range - with working examples going for north of £500. So I did the obvious thing and found a non working one locally for £125 instead. Which I figured was effectively £100 as I was saving about £30 on shipping.
This is otherwise known as "it was 4am, I couldn't sleep so wound up browsing eBay."
While it's externally complete and surprisingly free of physical damage, it was filthy. How can people use keyboards in this state? These keys should be bright white.
Needless to say that will be getting a good old scrub. As will the whole machine.
It never really instills confidence when you can see rust before you even take any covers off.
With the rear cover removed there was very clear evidence of this having been stored somewhere really damp for a long while. Plus lots of grime.
The immediate impression I got at this point was "Mmm...genuine barn find."
The motherboard actually looks fine. Grubby but there's no corrosion of any note actually on the motherboard I can see. Unlike many 386 era machines thankfully the CMOS battery is external and a primary lithium rather than Nicad actually on the board which usually leak. It's also just a standard type commonly used in cameras so I even have one in stock!
While the motherboard has seemingly escaped the corrosion, not everything else has been so lucky. Especially this poor hard drive.
That white gunk that looks kind of like mould? That's aluminium oxide. I have serious doubts about this drive coming back around. Which is something of a headache.
These drives are kind of an oddball. For a start, they're natively ESDI rather than anything commonplace like IDE or SCSI. However it's actually even worse than that - as the controller is physically attached to the drive, and it hooks directly up to the MCA bus on the motherboard. A system that IBM called Direct Bus Attachment (DBA). Which means finding a replacement will not be a five minute on eBay job. The most practical solution most likely would be to get a SCSI expansion card for one of the MCA slots and fit a SCSI drive.
That's getting a bit ahead of ourselves though - no point in worrying about a replacement hard drive if the rest of the system is a doorstop.
The seller had apparently tried to power it up, and had no life aside from the power supply fan.
Before I did anything I had to take it outside and attack it with the air line. The amount of finely atomised rust that I'm still brushing off my desk defies belief. It's not clean, but is a lot better.
Given I couldn't see any obvious issues and as I knew it had been powered up recently I figured that just plugging it in and checking our voltages was a good start.
Passed the first test: Didn't trip the RCD. Also the second test: Didn't blow up.
We had a working power supply fan, sensible voltages, the keyboard lights blinked when powered up, a working power light, and the hard disk did actually spin up. It also made some somewhat peculiar noises...but I don't know these drives well enough to have any idea what noises are normal. However nothing really useful. Zip on the display, either internal or external.
After a significant period of well...vaguely systematically poking, prodding, wiggling and cleaning connections we had progress, in the form of a beep code. Long, short, short. Which decodes to the primary display adapter being unable to start - which would indeed explain why we had nothing on the screen, assuming the plasma even worked - though I know the panel well enough to know it won't power up unless it sees a video signal. Helpfully it's exactly the same panel as Toshiba used on the T5200.
Some further fiddling around happened, then I noticed a lack of beeping, so looked at the screen.
Which on a reboot progressed to a memory test, showing 8 meg present - the maximum this could be specified with.
Then a 163 and 164 error listed (configuration options not set - expected with a 30+ year old battery). Then it did something I didn't expect - rather than complaining about a missing operating system, it booted into a BASIC prompt.
I'd forgotten some IBM machines had this built into ROM.
If these systems loose their BIOS configuration settings, they need to be booted from a disk with the configuration utility on - which IBM call the Reference Disk. Which brings us to the first thing I've found which definitely isn't working - the floppy drive. It seeks fine, but doesn't seem to be interested in actually reading data. It hunts a couple of times before just failing.
The drives in these things are reputed to be hugely unreliable - aside from being mounted vertically and having no slot door so they fill up with crud, they also have capacitor leakage issues. Of *course* these drives are non standard, because IBM. They have a combined power and data connection so I can't just drop another one in. Well until the adapter I've ordered arrives from the US arrives anyway.
I can't really do much else until that arrives and I can get the reference disk read, and find out if the hard drive has survived...I'm not giving it great odds, but I've been surprised before.
The keyboard however has been given a good clean so I no longer feel like I'm going to catch something just by looking at it.
Yes, that does look rather better.
This does use Alps key switches I can now confirm.
Which is quite interesting, as they feel very, very like the action of the buckling spring setup of the Model M, albeit with a slightly lighter action.
The display has now been removed from the machine so the driver board can be recapped.
Though I paused here because I discovered that IBM used security Torx screws to hold the cage on. I have a set of bits for them, but they're all the way down in the garage and I didn't have patience to go dig them out today. I'll need to track down where the 205V supply for the panel is generated in the machine as that will probably want similar treatment.
In terms of actual fleet news, things are afoot.
The decision has been made to move the camper on. It's barely moved in the last two years, and we really need something a bit bigger for our needs. I've pondered this a few times, but the decision has now been made.
Especially as I've just agreed to buy something else...and need to make space.
Easily the oldest car I've ever bought. Sort of thing I'd probably have walked past without a second thought ten years or so back, but have now really started to appreciate. This is all you're getting for now.
Should be interesting...and I'm really quite excited.
Sadly likely to be a couple of weeks before we have any movement on this as on Monday I'll be having to dash off to the US for a week to handle some family matters following a relation passing away a couple of weeks back. Why do these things always pop up at the most awkward times?
I'll be really interested to see the quality of photos it can produce. Excellent ones I'm thinking...
