UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Gemini 80-Bus System

JohnBHanson · 15th Sep 2019, 10:05 pm

loading the boot sector from cpm64w.bin - eg the sector starting with 47h 47h at address 0 and then executing from location 2 allows the system to boot.

The simon.rom from your website looks for a signature of 6dh 47h at the start of the boot sector. I think this is a special boot rom for the mfb system and hence fails. Patching the test to 47h 47h at offset 31h in simon.rom tries to boot from floppy.

There is code in simon to boot from the hard disk but I have not found out how to do it.

This does however indicate that the version of simon you have does not match the boot sector starting 47h 47h in cpm64w.bin

I have not managed to do anything with the first four sectors of that file...

Getting there...

15th Sep 2019, 10:05 pm	#222
JohnBHanson Heptode Join Date: Aug 2009 Location: Worthing, Sussex, UK. Posts: 662	Re: Gemini 80-Bus System loading the boot sector from cpm64w.bin - eg the sector starting with 47h 47h at address 0 and then executing from location 2 allows the system to boot. The simon.rom from your website looks for a signature of 6dh 47h at the start of the boot sector. I think this is a special boot rom for the mfb system and hence fails. Patching the test to 47h 47h at offset 31h in simon.rom tries to boot from floppy. There is code in simon to boot from the hard disk but I have not found out how to do it. This does however indicate that the version of simon you have does not match the boot sector starting 47h 47h in cpm64w.bin I have not managed to do anything with the first four sectors of that file... Getting there...