[Coco] Reading/Writing Model I/III/4 Disks on a CoCo

[Mark J. Blair]

On Sep 5, 2013, at 11:21 , billg999 at cs.uofs.edu wrote:
> Well, I don't know that I wold call it "booting".  It has a HEX
> loader that it can connect to the serial port.  But that lets you
> load a single program.  If you are good at Z80 assembler I suppose
> you could write a program that takes HEX input from the serial port
> and writes it to the disk.  That could make a way to move disk images
> on to the 4P.  If I had one I would probably try it (although I have
> more than enough machines that do 5.25" disks to use to make new
> 4P disks) just for the fun of it.  But I was never willing to pay
> the outrageous amounts people were getting for 4Ps.

That's exactly what I was thinking of doing. I'm not good at Z80 assembler (yet), and I don't even have any experience with the model I/III/4 yet... so that will make it challenging!

Yes, I've noticed how much people were asking for 4P systems on eBay. I got one for around $120 with shipping, and ignored the ones with asking prices of $400+ for bare machines with no software. Mine will be badly yellowed and missing the flippy door over the rear panel connectors.

On Sep 5, 2013, at 11:28 , Chris Osborn <fozztexx at fozztexx.com> wrote:
> Very interesting, can any of the other models do it? I found this:
> 
> http://www.hytherion.com/beattidp/comput/trs80.htm

I found that, too, and I've made email contact with the author. He says he'll try to find the old source code, and he's also contemplated writing something very similar to what I have in mind. So, maybe a new way to bootstrap newly-acquired model 4P computers will come into existence before long?

I don't know if other models can do it, or if it's just the 4P that has that feature. I think that it's just the 4P, but I'm not sure yet. For other model I/III/4 machines, I think that the cassette interface might be the easiest way to get an initial program onto the machine, just like we can do with DriveWire on the CoCo. The 4P doesn't have a cassette interface, so that's not an option on it.


-- 
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/