Mike's PCjr Page

How do you get the PCjr to recognize a serial mouse? I've been told that the CuteMouse driver is the best to uses so I downloaded that but it had a lot of files in the directory and I'm not sure which one to add to my config.sys file.

You'd just put ctmouse.exe in your autoexec.bat. I forget what options you need for the PCjr (I think you have to set switches for the address and IRQ since the PCjr has the whole COM1 at the address of COM2 thing going on unless the internal modem is installed), but you can play around with it on the command line before you add it to your system start-up.

Ah ok, I shall do that and see what happens. I think I have the switches needed written down around here somewhere.

How much memory does Cutemouse take? Between my backpack driver (13.5K) and Doskey (I love that history command), I'm worried that I'm going to reduce my free memory too low. I think it's at 586K or something right now.

From the Docs folder:

An important CuteMouse feature is its small memory footprint: the resident part (TSR) occupies less than 3.5K. CuteMouse can also install itself in upper memory, when available, without requiring external utilities such as the DOS 'lh' (loadhigh) command.

The file itself takes up about 6k on disk.

You can't load things into upper memory on the jr can you? I seem to recall doing that on my old DOS box back in the day.

Not in the traditional way, because using Upper Memory Blocks is a function of the 386's memory mapping capabilities. Some EMS cards may have been able to provide hardware UMBs which you could use to load device drivers, but such cards for the PCjr. would be extremely rare.

I believe that if you have a jrIDE, you can load device drivers in the "slow" 128KB of RAM with the JRCONFIG memory device driver.

Are there instructions somewhere on how to do that? Like Config.sys and autoexec.bat entries?

It could be done, there just currently isn't support for it. One could write a .SYS driver that would chain itself off the XMS interrupt vector and implement the HIGH memory calls. There is 48K of HIGH memory available on a stock JR w/ JR-IDE in the C segment. There can be another 128KB available if you replace a ROM on the MB (D & E segments). I think there is a UMB/HIGH memory driver project for 8086/88 public online. Might be a good place to start for an ambitious programmer.

GHiero wrote: I believe that if you have a jrIDE, you can load device drivers in the "slow" 128KB of RAM with the JRCONFIG memory device driver.

How does one go about doing that? Is there a special command that needs to be in the config.sys or autoexec.bat? I believe I already have the slow memory allocation activated.

Well I tried the mouse with Wasteland, but it doesn't seem to work. The mouse icon is there but I can't get it to move. I'm using the CuteMouse driver at COM 1/IRQ 3 so I'm not sure what's wrong. It might just be that the serial mouse I picked up isn't compatible with the PCjr. Either that or something is wrong with my serial cable (or the serial port on the jr).