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

JohnBHanson · 5th Oct 2020, 1:17 pm

My utility contains a copy of the hard disk boot sector code for the MFB system. It does not read the boot sector code of the disk. This boot sector code will be different to that for a non-mfb system.

I know that the boot sector code for the non-mfb system will *not* boot an
mfb system.

It does not read the boot sector code of the disk. I boot rom should after device initialisation read the boot sector code from the hard disk into ram and then copy 80h bytes down to location 0 and execute from location 2. This should allow the boot rom to boot either system. I think that the number of
the boot is held in register a (Not sure about this).

5th Oct 2020, 1:17 pm	#420
JohnBHanson Heptode Join Date: Aug 2009 Location: Worthing, Sussex, UK. Posts: 662	Re: Gemini 80-Bus System My utility contains a copy of the hard disk boot sector code for the MFB system. It does not read the boot sector code of the disk. This boot sector code will be different to that for a non-mfb system. I know that the boot sector code for the non-mfb system will not boot an mfb system. It does not read the boot sector code of the disk. I boot rom should after device initialisation read the boot sector code from the hard disk into ram and then copy 80h bytes down to location 0 and execute from location 2. This should allow the boot rom to boot either system. I think that the number of the boot is held in register a (Not sure about this).