On 1/31/2023 6:04 AM, Tony Duell via cctalk wrote:
"DLOAD is
the most obscure command in the Color
Computer and absorbs a substantial amount of space in the ROM. DLOAD is so
poorly
understood because Tandy has never made the necessary companion routine,
DSEND.
I wonder if it was originally intended (or even used) at the factory
to download a diagnostic program into the machine for final testing,
or for similar use at repair centres?
The IBM5150 has a similarly obscure facility to download a diagnostic
program through the keyboard port (this one is sort-of documented in
the BIOS sources)
-tony
It's always a possibility, but a dead test cart with the code would have
been a far better solution, and easier to implement, as the ROM is
permanent 9so to speak) on a home machine and would have had to go
through more QA.
I think (I might have mentioned it at the thread start) it was part of a
plan for a school network. Tandy offered a similar setup for schools
for the Model 1/3/4 systems, where the "host" could send programs, and
the clients would load from the common host system.
Jim
--
Jim Brain
brain(a)jbrain.com
www.jbrain.com