On 31/05/2014 19:42, Tommo H wrote:
I'm late to the party but congratulations from me!
I think I'd still sooner user a PC these days! ;-)
Now we can all more easily word process just like George R.R. Martin.
The original version of Pro-DOS was written before the large amount of reference material now available
Presumably you've got, or once had, some real, physical documents?
on the 'net. Back in 1991 my local reference library had a copy of the
original CP/M 2.2 user manual,
so I photocopied the "System Interface" section and used those photocopies as
my reference material. It
was all I had to go on at the time. I no longer have those photocopied sheets.
Today there is far more
CP/M reference material available, including the original CP/M 2.2 user manual
as a .PDF. As with *all*
of the programs I have ever written it was all trial and error really!
Certainly no formal methods and
no real planning. I just wrote the code as I went along. Something I've
always done and still do!
One website I found useful for technical reference was: http://www.seasip.demon.co.uk/Cpm/index.html
Perhaps the biggest difference between doing this rewrite and writing the original back in 1991 was the
availability of CP/M programs with which to perform system testing. Back in
'91 I relied on CP/M test
programs collected by Wayne Weedon, with many of those arriving on floppy disks
from software libraries
in the US. For this rewrite I had access to the huge "OAK" and "WALNUT CREEK"
archive CDs which are
both freely available on-line. These gave me much more scope for CP/M 2.2
It might be worth remembering that Pro-DOS isn't actually CP/M 2.2 but rather my interpretation of it.
For example, it doesn't have separate BIOS/BDOS sections like "real" CP/M and
is pretty much all one
These days I imagine it would be far simpler to take the original CP/M 2.2 and get that running on the
SAM. But "cheating" by using other people's code has never been for me.
Perhaps I'm a masochist!
In the future I'll be sticking to games. Far simpler, and no need to write a user manual either! ;-)