Re: A83: Grbuf again
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Re: A83: Grbuf again
In accordance with the prophecy, Scott Dial uttered:
> AHH... I am tired of people wasting 5 bytes! It is in the rom...
> lcd_busy is in the include file!
Yes, it's in the rom and the rom version is compatible with new, faster
versions of the ti-83 (I assume), _BUT_ TI documents that the routine that
causes the needed delay is:
push af
inc hl
dec hl
pop af
ret
together with a call to that routine. Calling the rom routine wastes several
clock cycles, which is why I used my own routine in Ride - The Demo.
However, these lcdbusy routines are not very lcd-driver friendly. Reading
port 10h and checking bit 7 would be the correct procedure, but would of
course be quite slow.
Linus
- --- Linus Akesson ------------------------ http://linusworld.cjb.net --- -
Those are my principles. If you don't like them I have others.
-- Groucho Marx
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