Mike's PCjr Page

Quick question. How do I get my jrIDE RTC to work with DOS 2.10? Not seeing this info anywhere. It does not save the date and time I put into it after each reboot.

You run the RTC.COM binary with a command-line option to store current DOS time into the RTC. Then in autoexec.bat you run "rtc /d" to have it set the time from the RTC.

Your next question is "where do I get rtc.com" and I believe the answer is https://www.retrotronics.org/home-page/jride/

Yup, that was easy! Thank you very much.

*cough* If someone - not naming names - but maybe initials 'MB' would add int 1A support to the BIOS *cough*

Sorry I need more vitamin C

The IBM PCjr BIOS? There's no room, it's packed pretty tight in there. Wait, you mean the ROM extension the jrIDE provides? Is there room?

One could write a device driver that would provide 1A services too, maybe for testing before committing to ROM.

Yes to the option ROM. There is plenty of room. 16K window and you can enable another 16K window that pans around the entire 512K flash.

I am assuming that if Int 1Ah has a non-error handler hooked before MSDOS starts, it will read and set the DOS clock automatically.

As the original author of the IDE portion of this BIOS, I had originally asked Mike to keep it closed source as it conflicted with some work that my company was doing at the time. That time has passed as the whole world has switched to uefi now, so I hereby grant permission to open it up to the public.
Maybe that will spark some interest into RTC support, better (more?) disk compatibility and bugfixes.

Can the BIOS of the jrIDE be changed (flashed?) without an eeprom burner?

Yes. There is a reflash utility on the project page. Also all source is in an SVN repo linked from the project page.

-Alan

Hargle wrote:As the original author of the IDE portion of this BIOS, I had originally asked Mike to keep it closed source as it conflicted with some work that my company was doing at the time. That time has passed as the whole world has switched to uefi now, so I hereby grant permission to open it up to the public.
Maybe that will spark some interest into RTC support, better (more?) disk compatibility and bugfixes.

Hi Hargle,

Excellent - I'll make prepping the code for distribution one of my winter projects. (I'm not the only person with the code; I've just been careful to ensure that it did not get widely shared until this restriction was clear.)

For anybody interested in the code; please give me a little time to get it ready.

-Mike