[Coco] Issues with NitrOS9 build

[Gene Heskett]

On Sunday 26 January 2014 18:49:12 Robert Gault did opine:

> Bob Devries wrote:
> > Gene,
> > 
> > I'm with you on that one.
> > 
> > I suggest an entry in rules.mak. That would mean just a single line
> > change in rules.mak at build time to change the value to 5.25" or
> > 3.5".
> > 
> > E.g. D80TRK=5
> > or D80TRK=3
> > 
> > and based on that, the 80 track descriptors should be correctly built,
> > and also the format command will select the correct DD.FMT value for
> > LSN0 for 5.25" or 3.5" at the discretion of the user/builder.
> > 
> > More thoughts anyone?
> > 
> > Regards, Bob Devries
> > Dalby, QLD, Australia
> 
> If you look in the technical section of OS-9 Level2 you will find that
> IT.TYP bit 0 is defined 0=5" floppy so you would expect 1=3.5" floppy.
> ITDNS is defined as bit0 0=FM 1=MFM, bit1 0=5" 48tpi 1=5" 96tpi. It
> does not seems to be explicitly stated but DD.FMT bit0 0=single sided
> 1=double sided bit1 is density.
> 
> NitrOS-9 has followed this convention and there is no need to change
> these definitions. What would make sense is to decide what format we
> want an 80-track disk to have. It seems reasonable to me that all
> 40-track disk images be 5.25" 48tpi disks and all 80-track disk images
> be 3.5" 135tpi. By convention in the current rbf.d file, 48tpi and
> 135tpi disks are both assigned DNS.STD while 96 tpi is assigned
> DNS.DTD.

Yes and no.  More bits are now in use than were when os9 was published.  
For the absolute last word, read the superdesc.asm file, which explains how 
the additional bits are now used.
 
> ==================
> It should be clear to all, that the initial report of this problem did
> not indicate anything about the actual hardware in use for drives.
> Please please everyone, in future when reporting problems present
> enough data for the problem to be solved. In this case, reporting a
> problem with DD.FMT and not indicating the version of NitrOS-9 in use,
> whether actual hardware or an emulator was used for testing, and what
> drive hardware was used made it impossible to formulate any theories.
> 
> Robert
> 
> 
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco


Cheers, Gene
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

NOTICE: Will pay 100 USD for an HP-4815A defective but
complete probe assembly.

Those who educate children well are more to be honored than parents, for
these only gave life, those the art of living well.
		-- Aristotle
A pen in the hand of this president is far more
dangerous than 200 million guns in the hands of
         law-abiding citizens.