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AT to XT Keyboard Converter

How often do you suppose the software will change? Do you anticipate working on it more and adding features etc?

If the anser is yes, then it is worth changing it around so it can be updated in circuit. Otherwise I'd say no, especially since from what I understand its a very simple program and design.
 
Chuck(G) said:
Good question. :)

Both approaches require a programmer; but the AVR programmer is a dirt-simple design that runs off the parallel port. And you don't have to use a socket.

On the other hand, the AVR takes up more real estate and would require at least a 6-pin programming header added, which might not make it possible to do a single-sided PCB.

Bottom line--I don't know. :tellme:
Click to expand...


Hi Chuck! Well, if you write up a schematic for me I'll give it a try as a single sided PCB. I'll add in a few zero ohm resistors if it gets too hairy. That will almost ensure it will fit on a single sided PCB.

Thanks and have a nice day!

Andrew Lynch
 
lutiana said:
How often do you suppose the software will change? Do you anticipate working on it more and adding features etc?
Click to expand...

I don't anticipate the program changing at all. But there's always the possibility that someone will say "I hooked it up with x keyboard to a y machine and it didn't work". One of the problems with developing hardware/software that will never go away, I guess.

lynchaj said:
Hi Chuck! Well, if you write up a schematic for me I'll give it a try as a single sided PCB. I'll add in a few zero ohm resistors if it gets too hairy. That will almost ensure it will fit on a single sided PCB.
Click to expand...

That's very generous of you, Andrew; however, we don't even know how well the current version will be received. If a demand develops for other keyboard conversions, it could potentially be the basis for another project.
 
Hi Chuck! We could spin up a PCB design "just in case" to see if its viable. Keeping it single sided *really* lowered the unit cost of the PCBs.

Thanks and have a nice day!

Andrew Lynch
 
well, I think I got some PICs programmed.
3rd computer, 3rd operating system (win98), 2 serial cables, and probably the 5th piece of software I've tried, I got a couple of them to verify correctly. Some won't program at all. Most of them seem to program differently, complaining about the oscillator value. I don't know what to do there, so I just used the defaults the software is suggesting.

Next problem up is that the mini connectors I ended up getting from digikey don't fit a regular mini keyboard cable! they are 5 pin alright, but there are actually 6 pins on a mini cable, and the connectors have the 6th hole filled in.
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=CP-2250-ND

so, I just happen to have an AT/XT switchable keyboard with the large 5 pin DIN connector on it, so I hooked it up, set it to AT mode, ran a midi cable out and over to my machine, and flipped the switch. the keyboard is getting power, as the numlock key flips the LED. If disconnected, the machines gives me a keyboard error for POST. However, no key presses are making it over to the machine.

I can only assume that the PICs aren't really programmed, or that oscillator value is causing it problems.

ugh. this project is fraught with disappointment. :angry:
 
Hargle, why don't I send you the unit I've got built up?

I'll even include a spare DIN cable to connect to your PC. Some of the MIDI cables do "crossovers" or don't have all 5 conductors done right.
 
Last edited:
Hi Hargle! Yes, what can I do to help? I can program PIC chips here if that would be helpful. Please let me know.

Thanks and have a nice day!

Andrew Lynch
 
thanks guys.

Since I owe andrew a PCB anyway, I will be shipping one+all the PICs to him for programming.

Thanks, but I don't think I need your module chuck; I'm pretty confident that it's just a bad PIC programming on my end that is the culprit. I also know my midi cable works-been using it on my 486 for years.

I'll get an RMA started on the digikey order too; maybe a little race between andrew and digikey to see who can get parts returned to me first!
 
Hi Chuck! Yes, I have the XT clone that I've used for testing the XT-IDE controllers. I haven't done anything with it lately but I will be glad to help out. Its been crazy busy with the N8VEM VDU in test, the 6809 IO mezzanine in development, and the S-100 IDE board project.

All I should need to test the AT2XTKBD is an AT keyboard and the XT clone, I think. These are bog standard PIC12F629s so my programmer should work. We used those devices for the hard sector simulator project you did a while back. Also I used a different PIC for the serial to parallel ASCII keyboard circuit project.

I just don't want to see the project implode over something like an uncooperative PIC programming device. The project just needs a little jump start and a bit of testing and it'll get rolling again.

Thanks and have a nice day!

Andrew Lynch
 
Thanks, Andrew!

You'll also give me another test point. I've checked the converter with an XT clone and an AT clone that's jumperable for XT keyboards. So far, so good--but I'm always expecting surprises. At least you'll be able to re-program the chip if you find something.
 
I'll keep my place in the queue waiting for the final product, even if I have two different programmers of which at least one supposedly should take most PICs. :)
 
Hi! Good news! I finally finished my build of the PCB that Hargle sent me. After some checkout and building a cable, I programmed one of the PICs and it works great! I plugged in an AT keyboard and the AT2XTKBD device into my old XT clone test station and it works just like you'd think it should.

I've programmed all the PICs and am getting ready to send it to Hargle for distribution. According to the programmer all the PIC programmed fine and the one I picked out works great. How much test do you want? I can test more if needed but if one is working then I think we are good to go. I can post pictures and/or more testing if needed but I'd really like to ship these soonest so I can move on to all the other projects I've fallen behind on!

Hargle, please PM me with your mailing address. I know I have it around here someplace but can't find it right now. Sorry this has taken me so long. I am just swamped lately!

Thanks and have a nice day!

Andrew Lynch
 
This has got me wondering what Hargle's problem was. I'd recommend trying this on a genuine vintage 5150 and 5160 before we allow it to escape. I've got a clone here, but you never know...

Fortunately, any incompatibility is likely to be a matter of programming only and these are tiny 8-pin DIPs, so shipping shouldn't be a problem.
 
Hi Chuck! I have a Genuine IBM XT motherboard in one of my test stations but it is buried at the moment and would be a major undertaking to unearth it. If your system and my system worked using a random build with whatever parts laying around, my guess is the design is sound.

I suppose there could be a IBM specific timing error or something but I'd bet Hargle was having issues with his programmer. Especially if the internal oscillator calibration value gets tweaked by the programmer, the PICs timing can get all messed up. I recall running into that problem before.

Well, I'd better get back to working on the XT-IDE update.

Thanks and have a nice day!

Andrew Lynch
 
Chuck(G) said:
[snip]


That'd work for me, as I have no interest in getting a quote for a tiny PCB with, what, a half-dozen components on it? Add a jumper header from pin 4 to ground for possible additional code for XT-to-AT mode. It's the features that get you, though. Some are going to want both 5 pin DIN and 6 pin mini-DIN on both input and output.

[snip]
Click to expand...

Hi Chuck! The jumper on the PCB is normally open for AT to XT conversion right? The PICs are on their way to Hargle so we should be hearing something soon on the AT2XTKBD project status. My board is working fine and all the PICs programmed OK, AFAIK.

Thanks and have a nice day!

Andrew Lynch
 
lynchaj said:
Hi Chuck! The jumper on the PCB is normally open for AT to XT conversion right? The PICs are on their way to Hargle so we should be hearing something soon on the AT2XTKBD project status. My board is working fine and all the PICs programmed OK, AFAIK.
Click to expand...

Hi Andrew!

Yes, that jumper's just there for future expansion. I'll keep my fingers crossed.
 
finally! I have success.

Andrew programmed up all the PICs for me, and I got them a couple days ago. Tested it out, and it worked perfectly. I think my programmer is junk. It was only $5 on ebay, so that may explain it.

So, over the weekend, I threw together a half dozen of the things. I have not yet tried them all out, but am confident that they will work, as the one I cobbled together a few weeks ago now works with andrew's PIC.

It looks like the total costs for them is $7 each. Not sure what shipping will be, but if I use a flat rate box in the USA, it's an even 5 bucks. I'm sure I could mail them for less than 1/2 that if I use 1st class and not the priority box.

I want to wait until after xmas to do any post office runs, so let me put together a final price list, including overseas customers and I will start taking orders in about 2 weeks. I will have them in both kit and assembled/tested form. Assembled and tested boards will be $10, kits are $7. You get what you pay for with regards to my soldering. ;) (no, honestly, my soldering isn't that bad, these are just easy to do)


yay! thanks to everyone who has stuck it out this long.

------
edit: oh yeah, it's weird and somewhat creepy to press the numlock key and not see the LED on the keyboard light up. I'm just not used to it that way, as that's typically my sign that the machine is accepting input. That's an XT for ya though! :)
 
Do you want to bundle this with the XT-IDE mailing? I can add another page to that spreadsheet for people to fill in, just let me know.

hargle said:
finally! I have success.

Andrew programmed up all the PICs for me, and I got them a couple days ago. Tested it out, and it worked perfectly. I think my programmer is junk. It was only $5 on ebay, so that may explain it.

So, over the weekend, I threw together a half dozen of the things. I have not yet tried them all out, but am confident that they will work, as the one I cobbled together a few weeks ago now works with andrew's PIC.

It looks like the total costs for them is $7 each. Not sure what shipping will be, but if I use a flat rate box in the USA, it's an even 5 bucks. I'm sure I could mail them for less than 1/2 that if I use 1st class and not the priority box.

I want to wait until after xmas to do any post office runs, so let me put together a final price list, including overseas customers and I will start taking orders in about 2 weeks. I will have them in both kit and assembled/tested form. Assembled and tested boards will be $10, kits are $7. You get what you pay for with regards to my soldering. ;) (no, honestly, my soldering isn't that bad, these are just easy to do)


yay! thanks to everyone who has stuck it out this long.

------
edit: oh yeah, it's weird and somewhat creepy to press the numlock key and not see the LED on the keyboard light up. I'm just not used to it that way, as that's typically my sign that the machine is accepting input. That's an XT for ya though! :)
Click to expand...
 
lutiana said:
Do you want to bundle this with the XT-IDE mailing? I can add another page to that spreadsheet for people to fill in, just let me know.
Click to expand...

that would be cool, and a great cost saver for anyone who is ordering both-essentially it means free shipping for 'em. I think there's only about 10 people interested in these though, but yeah, we can absolutely handle them at he same time.
 
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