DR-DOS 7.03 installation question

[MikeS]

It really sounds like you're confusing the Master Boot Record with the various OS boot records and system files.

The boot sector that the bootstrap loader is placed in is the very first sector of the disk(ette).

When the DR-DOS manual talks about location not being critical they are talking about the DOS system files, not the MBR; in early versions of DOS these did have to be at the beginning of the root directory (NOT the disk drive), i.e. within a bootable partition. The location of that partition is usually in the MBR and that MBR or at least a pointer to the MBR's location must normally be in the first sector of the disk in order for the BIOS to be able to find it.

See:
http://www.dewassoc.com/kbase/hard_drives/master_boot_record.htm

I suspect that Scandisk is actually telling you what you need to (but don't want to) know, namely that the disk drive indeed has unfixable errors...

If the first sector is OK but there is a hard error elsewhere on that physical track then being able to start the first partition on a specific higher "track" might work, at least for a while, but I'd think about replacing the drive instead...

 

[richo132]

It really sounds like you're confusing the Master Boot Record with the various OS boot records and system files.

The boot sector that the bootstrap loader is placed in is the very first sector of the disk(ette).

When the DR-DOS manual talks about location not being critical they are talking about the DOS system files, not the MBR; in early versions of DOS these did have to be at the beginning of the root directory (NOT the disk drive), i.e. within a bootable partition. The location of that partition is usually in the MBR and that MBR or at least a pointer to the MBR's location must normally be in the first sector of the disk in order for the BIOS to be able to find it.

See:
http://www.dewassoc.com/kbase/hard_drives/master_boot_record.htm

I suspect that Scandisk is actually telling you what you need to (but don't want to) know, namely that the disk drive indeed has unfixable errors...

If the first sector is OK but there is a hard error elsewhere on that physical track then being able to start the first partition on a specific higher "track" might work, at least for a while, but I'd think about replacing the drive instead...

Thanks for the info and advice.
I'd like to replace the Hard drive but the Toshiba BIOS only supports 3 drive types - pretty rare items.
Another problem is that the internal floppy drive will not read disks (26 pin I/F) - even rarer items.
I have been transferring the HDD to another PC to partition/format/load software.
Not sure how to do the DDO thing with this restriction.
Have tried putting in an 8bit FDC adaptor with its own BIOS to get a working floppy - but to no avail.
The 8 bit BIOS shows a message during boot indicating that the floppy is available and the T5200C tries but fails to read a floppy.
Curiously I get the same message as from the internal drive "Non-system disk or disk error. ..."

 

[Chuck(G)]

If you can find a floppy drive that fits the case, converting 26 to a 34 pin drive is comparatively simple.

With a DDO, it doesn't matter what the BIOS supports--the DDO takes over after the first track has been loaded.

 

[Caluser2000]

Interesting enough details of fdd pin convertion is on this thread- http://www.vintage-computer.com/vcforum/showthread.php?22058-Toshiba-T3100e-Memory-Upgrade

When you tried the FDD controller was the fdd selection in the computers bios disabled? Assuming it can be disabled.

 

[richo132]

Interesting enough details of fdd pin convertion is on this thread- http://www.vintage-computer.com/vcforum/showthread.php?22058-Toshiba-T3100e-Memory-Upgrade

When you tried the FDD controller was the fdd selection in the computers bios disabled? Assuming it can be disabled.

Unfortunately I could not find a way to disable the onboard FDC.
I did try 3 different addresses for the adapter card - but made no difference.
Thanks for the link to the 26-34 conversion - I had just discovered this link: http://www.martinruss.com/sy99adapter.html
and was going to ask whether anyone knows where to buy one of these ready made adapters.
However, I shouldn't be lazy - will make my own.
Please pardon my ignorance, but what does "pull-up" mean for pins 8&9 of the 26 pin side ?

 

[modem7]

Please pardon my ignorance, but what does "pull-up" mean for pins 8&9 of the 26 pin side ?

Pullup resistor - see http://www.seattlerobotics.org/encoder/mar97/basics.html

 

[Chuck(G)]

"Pull up" refers to a resistor connected between the signal in question and Vcc (usually +5). There are two reasons for this. The first is to make the default logic level of the pin with nothing connected a "high" value (particularly important with CMOS logic). The other reason, less used on modern equipment is to provide a return to Vcc of a line being driven by an open-collector driver.