Mike's PCjr Page

Going by memory, but I believe "-L" tells it to look for the extra memory

If there is extra room in a side car NIC, and the translation isn't a nightmare, a Keyboard port either PS/2 or physically USB. I say physically USB since it could be a keyboard only port. Maybe another port, PS/2 or USB, for a mouse.

On the Racore unit the J1 and J2 pins are the opposite of those on the the Rapport. J1 is i/o address and J2 is ROM address. The ROM addresses are also different. On J2 pins 1-2 is CC00 and pins 2-3 are C800. I went with C800 and setup the Racore as LPT2 I replace the Rapport Unit (with the bad para...

Here's one for any Racore Experts. I have a Rapport Drive II and a Racore Drive II (with DMA) . Both with different defects. The Rapport has a dead parallel port but otherwise works fine. Since the Racore Drive II is a DMA unit it came with a special floppy controller and that floppy controller is d...

Actually there are at least two current DOS virus scanners available. One is from Germany and one is from Russia. I have been using the German one but not on the PCjr as it requires a 386+ processor. What I have been doing, besides scanning new files, is copying the files from the PCjr onto a modern...

It required a separate power supply. I used another PC's keyboard port to supply the power for the test but I am going to cut the keyboard power tap and either feed it with a 5V wall adapter or tap into the light pin power. I looked at the tech ref and the light pen port provides +5v but only signal...

I finally got around to testing the parallel port CF card reader. It works. It is a DataFab Image Reader, Model MDCFE-SR. So far I've tested it with and 8 MB card but I should be able to use it with any card upto 32 MB since I am running DOS 3.3. It will be another way of getting data on and off the...

What strategy are you using for Virus prevention/detection? There seem to be very limited options for DOS virus detection and none that I found will work on anything less than a 386. The programs I have found are VirScan, a German DOS scanner, Dr. Web, a Russian Antivirus software company that makes...

Also try reseating all the socketed chips on the motherboard. I have seen them work there way loose on occassion.

Depending on what you are trying to do, and whether you get your PCjr going again, Qbasic's screen 7, might be a better way to go. If you are writing a program for Dosbox, Qbasic screen 7, will give you a 320x240 16 color screen. It won't work on the PCjr, although I haven't tried it. Even modifying...