Plus Keyboard Test?

[jwse30]

I've got a few Plus keyboards sitting here gathering dust, and I saw that there are a few people on the trading post forums looking for them. Is there a way to test these to see if they work if I don't have a Mac Plus or earlier machine? I don't really want to ship one out just to find out it's dead, and I don't want to ship in a Plus just to test them.

Thanks in advance,

J White

 

[Brett B.]

The only thing I can think of would be disassembling it and checking continuity on each switch. Beyond that, I think you'd need a compatible computer to do any further testing.

 

[CC_333]

Where are you located?

I have a couple Pluses which I can test these on. If you like, you can send them to me and I'll just try them out, noting any problems if some are found.

Shipping will be an issue though, but I think we could work it out somehow.

c

 

[jwse30]

Thanks for the offer, c.

Being in Indiana, I think the price of shipping would be a bit too high though. Perhaps I'll look into trying a continuity check x 100 or so :beige:

J White

 

[Brett B.]

Keep in mind that the continuity test will only test the switches themselves, not anything else. They are pretty hardy keyboards though. The M0110 I found for my Plus worked fine, apart from a broken switch on the 9 key. I took it apart to clean it and I swear there was an entire can of soda dried all over everything.

 

[insaneboy]

could just send me one, I'll test it with my keyboardless Plus... and I'll keep it if it works :lol:

 

[techknight]

Hook up power and ground to the keyboard, and check the data lines with a buffer and LED. Hold the keys, if the LED flickers with each key I guess its good? That or use a real mac.

 

[trag]

I'm pretty sure there's a little microcontroller built into the Mac Plus keyboard. Nothing short of connecting it to a Mac Plus or other compatible machine is really going to confirm that the MC is working properly.

So this got me curious. I did a little search and found one source which claimed that the Mac Plus keyboard contains an Intel 8021 MC and another source which says it contains an Intel 8049. They're both from the same family and the only difference is the amount of mask ROM and the number of IO pins available.

It would be interesting to hack the thing and read the contents of the program memory, to know exactly how the keyboard is meant to work. I think I'll go post that in Hacks as a suggested project. I'd add it to my list, but why bother? I'll never get to it...

 

[James1095]

Techknight's suggestion ought to work, at least it will tell you if the thing has some signs of life.

These things seem to be pretty sturdy though, I bet if you offer them as-is, they will fetch pretty close to the price they would tested working.