Date   : Mon, 09 Aug 2010 21:48:14 +0100
From   : afra@... (Phill Harvey-Smith)
Subject: Free Stuff Tranche III [Results]

Andrew Hancock wrote:
> I seem to recall there was a POKE on a Dragon 32, that could do the same
> thing! (She couldn't afford a Beeb!).
> 
> I tried it on my girlfriends Dragon, and it didn't break it!

Nope shouldn't cause it to break, though it may crash.

Poke &HFFD7,1 to go to faster mode
Poke &HFFD6,1 to go back to slow mode.

Also works on most Tandy CoCo machines as they and the Dragon are almost 
the same machine.

Basically the machine normally accesses memory at 0.98MHz, as the memory 
is shared between the CPU and the video chip, the poke tells the SAM 
(memory controler), to use 1.7MHz, when accessing memory above $8000, 
which is where the Dragon 32 (and the 64 in 32K mode) has it's rom, this 
has the effect of speeding up programs that run from this area, 
including the Basic interpreter.

Of course this doesn't work if the machine has 64K of RAM and is in all 
RAM mode.

There's actually another : poke &hFFD7,1 then poke &HFFD9,1 which will 
run the whole machine at 1.77MHz, but then it won't produce a display, 
and won't refresh the ram, so not very usefull :(

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.