Re: A89: Re: Frame Rates
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Re: A89: Re: Frame Rates
I actually tested this with a stopwatch-timed routine on my HW1 TI89, and
the rate the screen could be copied was about 770 times per second (I had
actually calculated 840 per second by adding up the amount of clock
cycles, but ... I think the timed value is more reliable). This was doing
MOVEMs of a line at a time, and with the loop partially unrolled (4 lines
per loop).
However, you won't actually see this kind of action, because the display
is not refreshed that quickly. Even if it were, the LCD wouldn't respond
fast enough. And even if it did, the human eye obviously isn't that fast.
However, for a TI-92, or a HW1 TI-89, the refresh rate of the LCD is once
every 16 increments of the programmable rate generator, or every 4
instances of interrupt 1, or every 100,000 clock cycles (see the hardware
documentation with Fargo II and DoorsOS). Assuming the actual clock rate
is exactly 10 Mhz, this gives a 100Hz display refresh, but the rate is
actually slightly lower than that.
As far as the actual LCD response, 4-color grayscale fully shows the
display in 3 refreshes, and still does not flicker, going at about 30 fps.
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