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PC XT keyboard compatibility, and XT-CF card?

J

JNZ

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Utah
I recently received an IBM PC XT, a 5150. I have an IBM Model M keyboard, P/N 1394054, the space-saving one. Weirdly it worked fine with an AT adapter--I was able to type in BASIC. Hopefully coincidentally it doesn't work now, after I tried to use a PC XT-CF ISA card and inserted it the wrong way. It blew out that cards EEPROM and I had to get a new one. (Seriously, why don't they have protection circuitry if it's so easy to reverse? I had boards on either side and couldn't see the orientation sticker.)

Is it expected that my AT keyboard worked on this XT for a time, and now doesn't? Do I need to buy the expensive XT keyboard to use this machine?

As a secondary issue, I can't get my XT-CF card to recognize this CF card, but there's little value in debugging it without being able to type.
 
JNZ said:
(Seriously, why don't they have protection circuitry if it's so easy to reverse? I had boards on either side and couldn't see the orientation sticker.)
Click to expand...

The metal ISA bracket is supposed to be the "protection circuitry" from reverse insertion. I know some of the cards out there don't have them, or are so "cost optimized" and small that you couldn't use one anyway.

JNZ said:
Is it expected that my AT keyboard worked on this XT for a time, and now doesn't? Do I need to buy the expensive XT keyboard to use this machine?
Click to expand...

I have had intermittent success with one of my autosensing Model Ms on my 5150. It works fine 100% of the time with my XT. I'm not sure what's different. I would not think that putting an ISA card in backwards should hurt your keyboard controller.
 
JNZ said:
I recently received an IBM PC XT, a 5150.
Click to expand...
???

IBM PC = 5150
IBM PC XT = 5160

JNZ said:
Is it expected that my AT keyboard worked on this XT for a time, and now doesn't? Do I need to buy the expensive XT keyboard to use this machine?
Click to expand...
No.
Your keyboard options are listed at http://minuszerodegrees.net
There is a [Keyboard Support] link in the IBM 5150 section, and one in the IBM 5160 section.
 
modem7 said:
???

IBM PC = 5150
IBM PC XT = 5160


No.
Your keyboard options are listed at http://minuszerodegrees.net
There is a [Keyboard Support] link in the IBM 5150 section, and one in the IBM 5160 section.
Click to expand...

The confusion comes because it's a 5150 that has a Microsoft Mach 10 8086 board, which made me think it was an XT for a while. Now I keep combining them.

The metal ISA bracket is supposed to be the "protection circuitry" from reverse insertion. I know some of the cards out there don't have them, or are so "cost optimized" and small that you couldn't use one anyway.
Click to expand...

I think I'll post a review of the XT-CF once I get it working. But one of my main complaints is that it has no mechanical safeguard to protect it from being inserted the wrong way (nor does it even have space for an optional bracket to be attached), nor are there electrical protections. There's a sticker that indicates the orientation, but that's only visible on one side, so if you're unlucky like me and have other cards blocking it when you insert it, you won't see the warning sticker. The cost of inserting it backwards is that you immediately fry the EEPROM. Not good!

The site I bought it from sent me a new EEPROM free of charge, which was nice, but they also censored my review that listed all these faults. To date the review I posted never passed the approval process the site said it needed, even though I mentioned it twice in the emails to the site's owners when they offered to send me a new EEPROM.
I think they're an honest company with good owners (and are serving a niche market), but if I had seen a review like mine I might've been more careful and avoided the whole situation to begin with. Plus what right do they have to keep people from learning about some real drawbacks of that product?

Anyway, I'll check the keyboard compatibility guide and try to find a reasonably priced option for me. I would've preferred if I had gotten a PC AT, but this computer was given to me for the cost of shipping, which was too good to pass up.
 
JNZ said:
...But one of my main complaints is that it has no mechanical safeguard to protect it from being inserted the wrong way (nor does it even have space for an optional bracket to be attached),...
Click to expand...
Doesn't the component side v. the solder side of the card make it logically impossible to insert it the wrong way?
 
JNZ said:
The site I bought it from sent me a new EEPROM free of charge, which was nice, but they also censored my review that listed all these faults. To date the review I posted never passed the approval process the site said it needed, even though I mentioned it twice in the emails to the site's owners when they offered to send me a new EEPROM.
I think they're an honest company with good owners (and are serving a niche market), but if I had seen a review like mine I might've been more careful and avoided the whole situation to begin with. Plus what right do they have to keep people from learning about some real drawbacks of that product?
Click to expand...

That's unfortunate. It's a valid concern, and I could see it being an easily made mistake, especially if you were testing the card in a later machine with all/mostly PCI cards.
 
Stone said:
Doesn't the component side v. the solder side of the card make it logically impossible to insert it the wrong way?
Click to expand...

Logically impossible? I suppose so, because the EEPROM let out magic smoke. It wasn't mechanically impossible to insert it the wrong way, however, and there were no safeguards against doing so, apart from a sticker that I wasn't able to see in my computer's configuration.

I had actually inserted it the right way to begin with, but my CF card configuration didn't work, leading to me being distracted by debugging. I had removed the card for a bit and then went to reinsert it in a different slot, and this time didn't check the orientation.
 
JNZ said:
....I had removed the card for a bit and then went to reinsert it in a different slot, and this time didn't check the orientation.
Click to expand...
It's easily done and has been done by other's, I did it once myself, I was watching TV at the time and never had my mind on what i was doing, Totally my fault, Luckily i had spare EEprom and it was good again in no time, They have their uses especially in machines with little space available.
 
glitch said:
I would not think that putting an ISA card in backwards should hurt your keyboard controller.
Click to expand...

If it worked before and doesn't work now, that would be exactly my concern. I'd take a close look at the motherboard near the keyboard input. It's a shame that testing the AT keyboard on another machine or testing an XT keyboard aren't simple options unless you own a bunch of vintage hardware. Maybe someone here knows how to check the keyboard input with a multimeter but of course if you don't have a multimeter then that's not a simple task either.
 
maxtherabbit said:
it certainly should, if you're paying a modicum of attention to what you're doing
Click to expand...

Ah yes, I remember now. I wasn't paying a modicum of attention to what I was doing. Just pissing into the wind and slapping cards into this expensive old computer.
 
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