[Coco] Nitros9 technical question....

[Gene Heskett]

On Monday 11 November 2019 08:11:15 Robert Gault wrote:

> Phil,
>
> This list ought to be as good as anything else but you can try:
> https://sourceforge.net/projects/nitros9/
> Look at the Support and Discussion panels.
>
> Regards your specific question, you could study the current NitrOS-9
> disk I/O code as it also needs to deal with simultaneous disk access
> when more than one program is running. I assume that the disk code
> should ask the system for permission to access a disk and/or the
> system should keep track of the number of current requests for disk
> access.
> Either disk or system code would, in your case, then keep track of the
> A/O AVR values and prevent cross routing.
>
> Robert
>
> Phill Harvey-Smith wrote:
> > Hi all,
> >
> > Is there still a Nitros mailing list that might be a more
> > appropriate place for this?
> >
> > Anyway I have a mostly working boot & disk driver for the DragonMMC
> > interface, which can boot and access any mounted disk images. What I
> > want to do is to convert the ROM utilities that allow you to list
> > the contents of the SD card, and mount / unmount images to command
> > line utilities for Nitros.
> >
> > The DragonMMC works by having the FAT & SD reading part of the
> > system handled by and AVR microcontroller, the 6809 side of things
> > uses a set of I/O locations to exchange data with the AVR. This
> > works for the disk driver code, and would be able to work for the
> > utility code, however being a multi-tasking OS I need to ensure the
> > utilities don't interfere with disk I/O that may be going on in the
> > background.
> >
> > Does anyone have any suggestions as to the correct way to do this?
> >
disk access is controlled on a sector address granularity, so its 
entirely possible to start an assembly, give it time to write the first 
sector of the listing, and start a list of that file, and the lister 
will stay one sector behind the assembler until the assembler is 
finished and closes the file, at which point the last sector will be 
listed.
> > Cheers.
> >
> > Phill.


Cheers, Gene Heskett
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