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Ozfer
February 23rd, 2014, 05:48 PM
Hey guys I'm still working on my 5150 project and I have made some progress since my lasts posts and now I have a Model F keyboard and a working VGA card connected to a monitor.

Now when I start the computer up it goes into IBM basic and I can't use the keyboard. I have it plugged into the "keyboard" port and the guy I bought it from knows that it works. Also sometimes I see a random character appear on the screen and I'm not sure what causes it. It is probably an issue with the pc but I have no idea what. Any Ideas?

Also sometimes I get parity error 2. It happens randomly and I have no idea why. Sometimes it boots up fine without parity error and sometimes it gets parity error.

modem7
February 23rd, 2014, 09:44 PM
and now I have a Model F keyboard ... and I can't use the keyboard. I have it plugged into the "keyboard" port and the guy I bought it from knows that it works.
I presume that you are seeing a 301 error on-screen at boot time. Are you?

Per http://deskthority.net/wiki/IBM_Model_F, model F' keyboards cover quite a range of keyboards, and includes one for the IBM AT. So, do you know that yours is one for the PC or XT, and not AT ?


It is probably an issue with the pc but I have no idea what. Any Ideas?
See note 13 at the bottom of http://www.minuszerodegrees.net/5150/misc/5150_post_and_initialisation.htm

Ideally, obtain a second XT-class keyboard, and then quickly prove either the keyboard or motherboard at fault.

Assuming that your keyboard is an XT-class one, and that it is good, something that may (repeat: may) reveal a cracked solder joint on the motherboard's keyboard connector, is to power up the 5150 multiple times, each time holding the keyboard's connector at a slightly different angle.


Also sometimes I get parity error 2. It happens randomly and I have no idea why. Sometimes it boots up fine without parity error and sometimes it gets parity error.
If the motherboard switches in your 5150 are configured properly, then PARITY ERROR 2 results from a RAM parity error on an expansion card that provides RAM. I suggest that the first thing you try is to re-seat all RAM chips on the expansion card/s that is/are providing RAM.

Ozfer
February 24th, 2014, 03:01 AM
Okay it does have a expansion ram card and I will try that. Wow I didn't know those were error codes since it never beeped or anything but it does say this when booting up.

6020 201
301
131

Possible causes:
1. It cant be that its not compatible.
2. Its in the keyboard port.
3. The keyboard is attached.
4. It has been tested working.
5. It has been tested working.
6. It has been tested working.
7. Faulty motherboard - bad solder joint on keyboard connector.
8. Faulty motherboard - faulty keyboard circuitry.

Oh yay now what do I do :/ I don't really just have a second XT keyboard laying around. I will try some things later when I get some time.

Stone
February 24th, 2014, 03:49 AM
Since you know the keyboard to be working it's likely not an XT keyboard.

Compgeke
February 24th, 2014, 05:41 AM
Would you mind uploading a picture of the keyboard? That can help verify if the keyboard you have is correct or not.

luvit
February 24th, 2014, 05:42 AM
Yeah, I think Stone is trying to say that if the previous ownder of the keyboard knows that it's a good keyboard, it's unlikely that it was recently tested on a XT machine.
Not many people keep an XT machine around.

Stone
February 24th, 2014, 06:50 AM
Not many people keep an XT machine around.Almost everybody here does. :-)

luvit
February 24th, 2014, 08:02 AM
yeah. lol. i;m thinking of the source from where he got his keyboard.
i lost my XT in a flood 10yrs ago.. I'm getting it replaced this week!! :):)

Ozfer
February 24th, 2014, 09:03 AM
It does say IBM personal computer on it. Here are some pics (I couldn't get the site upload thing to work so I had to put them on dropbox)

https://www.dropbox.com/s/gwcnq3iv0ccbeph/IMG_0273.JPG

https://www.dropbox.com/s/7wwsmzgp8kl6l28/IMG_0274.JPG

https://www.dropbox.com/s/okrri0snzuhip7h/IMG_0277.JPG



Also note that I get the same errors regardless of if I have a keyboard attached.

Stone
February 24th, 2014, 09:33 AM
I have that exact keyboard. It's the 83 key model from the PC series. It's not AT compatible.

SpidersWeb
February 24th, 2014, 10:24 AM
If there was a code following the 301 I'd suggest the keyboard might have been damaged in shipping e.g. a plate slipped but there wasn't.
You'll need to test it out on another XT that you know works. (Which I figure you don't have, so that's a bit of a pain).

Edit: looking back, I'd follow what modem7 suggested.

Ozfer
February 24th, 2014, 11:45 AM
It says IBM personal computer and my 5150 says IBM personal computer and they have the same connector but they don't work together ? D: I also bought a ps2 adapter and that didn't seem to work either but I blamed the adapter since it was cheap. It always gets the same error code no matter what I have plugged in or if I don't have anything plugged in.

I thought this IS the pc series this doesn't have a 286 and it is a 5150 shouldn't it work?

Blinkenlightz
February 24th, 2014, 04:04 PM
From your pictures, I recognize that as an XT-class keyboard (Identical to all the ones I've seen, including my own which works on a 5150 and 5160), so it should be compatible with the 5150.

A PS/2 keyboard with an adapter certainly** won't be compatible. The two basic types of PC keyboard are XT and AT. All PS/2 keyboards are AT-compatible as far as I know. I've never encountered a PS/2 keyboard that is XT-compatible.

Some AT keyboards have an XT/AT mode switch, and can be used on either (the connector is the same).

Assuming from the above that your keyboard is in fact 5150-compatible, I'd start looking for either a faulty motherboard keyboard connector, faulty keyboard cable or connector, corroded pins, or similar. Maybe someone can chime in as to whether the 5150 has a keyboard BIOS that could have failed...


**See Stone's comment below... Model M PS/2 keyboards may still support XT/AT autosensing

k2x4b524[
February 24th, 2014, 05:20 PM
I would be looking at the keyboard controller, or the connector on the motherboard. As that keyboard was good when it left, as verified by IBM Advanced Diagnostics, otherwise I wouldn't have released it into the wild. Could one of the other boards in the machine be interfering with the operation of the keyboard?

Stone
February 24th, 2014, 05:30 PM
I've never encountered a PS/2 keyboard that is XT-compatible.

Some AT keyboards have an XT/AT mode switch, and can be used on either (the connector is the same).Certain Model M keyboards (maybe most of them) are AT, PS/2, and XT (via autosensing) compatible.

Blinkenlightz
February 24th, 2014, 05:43 PM
Certain Model M keyboards (maybe most of them) are AT, PS/2, and XT (via autosensing) compatible.

I stand corrected - I'll have to try that sometime...

Compgeke
February 24th, 2014, 06:19 PM
Easiest way to tell a XT compatible Model M is a silver badge in the top left rather than a circular IBM logo. Unfortunately they aren't very common.

modem7
February 24th, 2014, 09:01 PM
Maybe someone can chime in as to whether the 5150 has a keyboard BIOS that could have failed...

I would be looking at the keyboard controller, or the connector on the motherboard. As that keyboard was good when it left, ...
Unlike the IBM 5170, the 5150 (and 5160) do not have a keyboard controller chip on the motherboard.

modem7
February 24th, 2014, 09:25 PM
Okay it does have a expansion ram card and I will try that. Wow I didn't know those were error codes since it never beeped or anything but it does say this when booting up.

6020 201
301
131

"6020 201" --> RAM error in bit 5 at address 384 KB.


"301" --> Keyboard error (POST did not receive byte AA from keyboard within required timeframe).

The earlier emails have established that your keyboard is good and is compatible with the 5150.
That leaves a bad solder joint on the motherboard or faulty keyboard circuitry on the motherboard.

The earlier post [here (http://www.vintage-computer.com/vcforum/showthread.php?39264-5150-Keyboard-Malfunctioning)] is an example of a 5150 owner discovering a bad solder joint on the motherboard's keyboard connector.


"131" --> Cassette port problem.

See note 12 at the bottom of [here (http://www.minuszerodegrees.net/5150/misc/5150_post_and_initialisation.htm)].
There has been at least one VCF user who got rid of the 131 error by reseating plug P9 from power supply.

k2x4b524[
February 24th, 2014, 09:32 PM
Thank you for pointing that one out. I've been under the impression that the XT had a keyboard controller, not just the circuitry to make it work. What chips on the XT motherboard control the keyboard?

modem7
February 24th, 2014, 09:41 PM
Thank you for pointing that one out. I've been under the impression that the XT had a keyboard controller, not just the circuitry to make it work. What chips on the XT motherboard control the keyboard?
See page 4-4 of the APR84 edition of the IBM Technical Reference for the 5150 (available [here (http://www.minuszerodegrees.net/manuals.htm#IBM)]).

Stone
February 25th, 2014, 03:19 AM
Easiest way to tell a XT compatible Model M is a silver badge in the top left rather than a circular IBM logo. Unfortunately they aren't very common.The badge is actually in the top right. I'm using one now. :-) Also, there are no lights on this keyboard. It's this (http://www.clickykeyboards.com/index.cfm/fa/items.main/parentcat/9231/subcatid/0/id/112510) one, Part No 1390120.

Ozfer
March 5th, 2014, 11:38 AM
The keyboard I have is a model F and it is compatible with the 5150. It is identicle to one that would have been sold with it. I found the issue with my system was the extra ram card I have installed. When I don't plug it in and set jumpers to 256K memory the system boots up and types fine. When I plug it in all the issues start happening. Later I will see what I can do about resocketing stuff and fixing the extra ram card. For now I am happy my system is finally fully working. :)

bettablue
March 6th, 2014, 03:51 PM
Would you mind uploading a picture of the keyboard? That can help verify if the keyboard you have is correct or not.

When taking photos, its always a good idea to get pics of the top AND the bottom of the keyboard.

Just my 2 cents worth.