Nextor and format command

By JunSoft

Resident (34)

JunSoft's picture

21-08-2018, 10:09

I'm currently writing a Nextor Drive-based driver for my new hardware.
Now Read operations are OK. (I can read files in a disk)
But 'format' API(416CH) seems not working. Is this a known bug? Or did I miss something?
Or is there any compatibility problem to OCM?
Any hint is welcome.
Thanks in advance.

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By luppie

Paladin (854)

luppie's picture

21-08-2018, 16:13

afaik the format command on the OCM isn't supported, when the mega-sd (DIP8) is enabled.
I had the same problem using an external diskdrive interface with my OCM

You can try disabling the mega-sd

By JunSoft

Resident (34)

JunSoft's picture

22-08-2018, 14:23

Thank you for the reply. But it seems not the case.
The problem is that "format" API is not called.

By luppie

Paladin (854)

luppie's picture

22-08-2018, 22:12

What I mean is the following:

The format command is working, but calling the underling API is disabled when the mega-sd is enabled:


Maybe KdL can also comment on this, he knows the OCM PLD the best.

By JunSoft

Resident (34)

JunSoft's picture

23-08-2018, 03:03

Yes, that's the point. Who prevents calling "format" API?
In my case, two disk kernels exist, Nextor and mega-sd. And nextor.sys is loaded instead of msxdos2.sys.
When I use format command in DOS, I get same (or similar, I can't remember exactly at this moment) message
for the internal OCM drives ('B:'). But for a new drive I'm developing ('A:'), the situation is different.
The "choice" API is called, as I expected. The choice message is also shown.
I can type '1' or '2'. But the "format" API is never called...

I also tested that after disabled mega-sd. In this case, no boot-able media found and OCM enters basic mode.
When I use "call format", the choice message is shown but format API is not executed again.

There may be a bug in my code. I want to know this situation is abnormal for my case.