[Color Computer][Coco] DLOAD mystery

[Paul T. Barton]

Here it is:
DLOADM Bug

      The mystery surrounding the DLOADM command in Extended Color Basic as
discussed in "CC DLOAD" (80 Micro, March 1983, p. 140) is easily cleared up. A
bug in the ROMs prevents a DLOADM command from being recognized as such.

      For a simple fix, use

CLOSE #-l : POKE &H78, ASC("M"): DLOADM "filename," baud, offset.

Baud has the same value as DLOAD and offset has the same value as CLOADM.

      As with CSAVEM and CLOADM, there is no DLOADM token, just DLOAD followed
by an ASCII M. On encountering a DLOAD or DLOADM command, the next byte from
the Basic program loads into the A register (an ASCII M if the command was
DLOADM). This first step is common to most commands and occurs before jumping
to the DLOAD routine.

      Second, a subroutine closes the cassette file if it’s open (DLOAD or
DLOADM needs the buffer). Then the A register is checked to see if it contains
an ASCII M, and a flag byte is set or cleared accordingly.

      Unfortunately, the second step causes the contents of the A register to
change; consequently, the third step does not recognize DLOADM. This bug could
have been corrected by exchanging the second step for the third.

Ralph Fox

4212 Wadsworth Ct. #102

Annandale, VA 22003

 
----

--- Gene Heskett <gene.heskett at verizon.net> wrote:

> On Tuesday 07 March 2006 00:26, Neil Morrison wrote:
> >----- Original Message -----
> >
> >> http://groups.yahoo.com/group/ColorComputer/files/DLOADM Bug.htm
> >
> >Should be
> > http://groups.yahoo.com/group/ColorComputer/files/DLOADM%20Bug.htm
> 
> Uh huh, and it takes a yahoo login to access it. I don't think I have 
> one of those puppies.
> 
> -- 
> Cheers, Gene
> People having trouble with vz bouncing email to me should add the word
> 'online' between the 'verizon', and the dot which bypasses vz's
> stupid bounce rules.  I do use spamassassin too. :-)
> Yahoo.com and AOL/TW attorneys please note, additions to the above
> message by Gene Heskett are:
> Copyright 2006 by Maurice Eugene Heskett, all rights reserved.
> 
> -- 
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
> 


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