[Coco] TC-9

[L. Curtis Boyle]

On Mon, 07 Jul 2008 14:23:19 -0600, Frank Swygert <farna at att.net> wrote:

> I recall the TC-9 using the GIME. The reason was for 100% OS-9 Level II  
> compatibility, and there was hope for some DECB 2.1 compatibility (CoCo  
> 3 only). The later never occurred, too many hardware differences I  
> think. Easy enough to tweak an OS-9 driver for minor differences, DECB  
> was harder to patch.
Yes, it used the GIME, and a standard 28.xx MHz clock (I overclocked mine  
with a 32MHz crystal). If you bought the TC-9 prepackaged (like Bill Nobel  
& did), it came with a cable that switched the weird inverted connector to  
a standard cartridge port connector (your choice if you got a single or Y  
cable one, but if you were using the Y cable, you had to make sure that  
you're floppy controller was fully decoded). I ran mine with the stock  
Tandy floppy controller and a B&B hard drive (60MB) for years. Ran it with  
the 1MB RAM daughter board as well. Bill & I completely redid the  
keyboard/mouse/sound driver (TC9IO, which replaced CC3IO), from the  
original version by Bruce Isted. We added support for Numlock/Caps lock  
controllable by each window (instead of system wide), 8 bit sound support,  
and a bunch of keyboard updates, from what I remember.
     The RSDOS first version ROM (a replacement, larger ROM image than the  
original version it shipped with) was done, and was written by Chris  
Burke, but I could never get it running stably on my system (whether this  
was due to the overclock or not, I never did dig in deep enough to find  
out). We did some minor tweaks to the Serial port driver (dual port 6552,  
capable of up to 38400), but we did modify the mouse routines somewhat (3  
button support was started for Logitech mice, I believe). It did boot a  
few times enough for me to type in a small BASIC program, but it always  
crash on me. There was also boot rom versions that booted from the  
Eliminator or B&B hard drive systems, as well as the floppy. I did mine  
off of floppy because of development (always had a stable floppy complete  
boot to reboot from is something went horribly wrong).

>
> There's an interview with Frank Hogg and I think a pic of a TC-9 in  
> "Tandy's Little Wonder", downloadable from the maltedmedia site  
> (ftp://maltedmedia.com/coco/Farna/Tandy's%20Little%20Wonder/Cocobook-TLW2.pdf).  
> I recorded a conversation with Frank Hogg about his CoCo involvement and  
> wrote the article from that interview tape. Wish I still had the  
> original cassette!
>



-- 
L. Curtis Boyle