GEOS Kernal Construction Set

A few years ago I started experimenting with an old GEOS 128 ROM image available on the internet, with the idea of installing it permanently into my C128. After trying it out on Vice, I was quite disappointed. Not only was it slow to decompress in memory, but filled the screen with garbage and didn't handle the 40/80-column key properly. The main problem seemed to be it was based on a memory dump which carried lots of garbage. So I set about creating a new ROM image from my original disks.

Then I had to change houses and the project remained frozen for a while. Last year I came across my working files and decided to go back to the drawing board, but after toying around with many ideas, I came to the conclusion it would be nearly impossible to do a one-size-fits-all ROM, and so GEOS Kernal Construction Set was born. It allows you to build a customized GEOS 128 2.0 kernal, with your very own serial number, and specify which drive type and device number it will boot auto-execs and the deskTop from.

Additionally, you can choose a different default input driver (currently 1351 mouse, standard and accelerated), and support for either Commodore 17xx REUs or GEORAM (and compatible) memory expansions. The first public version has been up since January 2022 at peeknpoke.com.ar/gkcs, and today I have added the German-language editions, which led me to introduce the tool in this forum.

Feel free to experiment but keep in mind it's still under development, so there are still some rough edges. Comments and suggestions are certainly welcome!

First of all, thank you for trying out GKCS and providing such detailed feedback.

Zitat von darkvision

Drive#8 includes a disk with mouse driver, 128 DESKTOP and 128CONFIGURE.

If you select a 1351 mouse driver when building your kernal, you can do without an on-disk input driver.

Zitat von darkvision

Drive#9 is optional... i have tested if i can use the ROM to upgrade to GEOS/MP3... works! Of course you need a newer TopDesk to support newer Hardware... was a bit tricky to get it to work.

This is insightful. I'm not at all familiar with GEOS/MP3 (or even Wheels for that matter). I have plans to include the gateWay 2.0 Kernal once I finish work on the standard one. I will take time to learn about MegaPatch and see if there are patches that could be applied in advance to a ROM version.

Zitat von darkvision

When booting up VICE hold down CTRL brings up the GEOS desktop... without 128CONFIGURE you will not get a RAM1571. With 128CONFIGURE the size of the REU depends on the version of CONFIGURE.

That's absolutely correct. GEOS Kernal, Configure 2.x and deskTop (to a lesser degree) are tightly integrated. Upon boot, the GEOS Kernal includes a copy-protected 1541 driver (yes, even for GEOS 128) which allows the startup routines to look for auto-exec files. Configure 2.x takes care of setting up proper disk drivers, detecting RAM expansions and eventually a RAM drive. Finally, the deskTop loads the first input driver on disk, overwriting the joystick one included as default with the Kernal.

Zitat von darkvision

Nice Work!

Thank you!

Hello, JHKrueger.

I'm terribly sorry for replying this late, but it's been a while since I last checked Forum64. Luckily, the reason GKCS was not working was a silly script error, which I now have fixed. I apollogize for the frustration a non-working tool may have caused. Please try it out again, and let me know if you have any suggestions, comments, etc.

Regards!