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Re: Request: Hard-sectored disks (5.25) for test material to KF team

Posted: Sun May 19, 2019 9:25 pm
by aquarius
Prologue (QMOS) is started with the command B:0,8

Where the 0 stands for Drive 0; if you put in B:1,8 it boots from Drive 1.
The second number must be the boottrack or bootsector.

The G: Command is for direct jumping to a address in memory e.g. G:0100

The T: command is unknown to me.

Re: Request: Hard-sectored disks (5.25) for test material to KF team

Posted: Sun May 02, 2021 10:44 am
by aquarius
ZrX wrote: Tue May 14, 2019 7:14 pm After having looked at two Questar disk dumps the format seems as follows:

- 2 sides
- 80 tracks per side
- 16 sectors per track (0-15 on side 0, 16-31 on side 1)
- 256 bytes per sector
- 300 rpm
- MFM sync ...AAAA AAAA AA91 2AAA (bytes 00 00 05 00)
- Decoded track format 05 00 TT SS + data*256 + two checksum bytes + padding
- First checksum byte is TT + SS + data + overflows of the calculation
- Second checksum byte calculation not solved yet
Hello @ZrX and others,

there is new work done on vzekc.de with hard-sectored floppyformats.

The second checksum seems to be resolved right now in this hour.

Re: Request: Hard-sectored disks (5.25) for test material to KF team

Posted: Mon May 03, 2021 9:39 pm
by ZrX
Not really being fluent with german language it's difficult to find where to look. :)

Re: Request: Hard-sectored disks (5.25) for test material to KF team

Posted: Mon May 03, 2021 10:16 pm
by aquarius
@PAW of Vzekc managed to find out the algorythm for the second checksum.

As far as I understood, it is a consecutive summation of all the results of the previous summations.

Do you have dumps of other Micral discs by the way? It would be great to bring the R2E software and hardware togeather.

Regards
Aquarius