Mike's PCjr Page

Sorting through my box of PCjr stuff and would like to know what these items are. Anyone?

You have a modem, an 8087 coprocessor daughter board, and wrap plugs from the maintenance manual there. Oh, and a loose BIOS ROM chip.

I have never seen the coprocessor daughter board in real life. Take good care of it, it is extremely rare.

Thanks! .. couple other items:

I think this other board is a controller for a floppy drive?

The description for the cartridges is insulting.. the PCjr is not a real PC? (I know what they meant though!)

While I got you on the line.. (EDIT: As in phone line, not fish line! )

Is this mouse and pad only used for the Colorpaint Cartridge Software?

Hmmmm...methinks I smell the scent of troll in the air.

OldComputerGuy wrote:Hmmmm...methinks I smell the scent of troll in the air.

Sorry you think that, but I'm serious as a heart attack!

You're not one of those forum bullies are you?

That looks a floppy controller for the PCjr. I don't know the IBM part number off the top of my head; other vendors made replacement controllers.

The cartridges are interesting but I've not had to use one often. There was some software that checked the machine "ID" byte in ROM to see if it was on a PC or a PCjr; the cartridges can be used to fake the software into thinking that they are on a real IBM PC 5150.

The mouse pad is required to use the mouse no matter what program you are using. That's how optical mice used to work back then. You find this interesting for background: http://www.brutman.com/Mouse_Systems_Op ... Mouse.html


Mike

Thanks! That concludes my unknown Hardware. I'm waiting for a keyboard that I bought from a forum member and then I can start asking a lot more questions when I attempt to get it going.

Brutman wrote: You find this interesting for background: http://www.brutman.com/Mouse_Systems_Op ... Mouse.html


Mike

Nicely written Mike.. very informative.

Brutman wrote:You have a modem, an 8087 coprocessor daughter board, and wrap plugs from the maintenance manual there. Oh, and a loose BIOS ROM chip.

I have never seen the coprocessor daughter board in real life. Take good care of it, it is extremely rare.

Is that a modem? It has an RJ jack of some kind, but it just says 'serial interface' and I don't see any hardware on there that looks like it would be related to modulation/demodulation. It does have a couple of MC1489s on board, though, which were frequently used in RS-232 circuits. I think it might literally be just a second COM port that happens to use an RJ jack as a connector instead of a D-Sub.