Scali
Veteran Member
Here you are:
Hum... interesting. At least it is consistent.
But what I don't get is why it gets such high values.
What machine are you running this on?
Because if your PIT is indeed running at 1.19 MHz, as it should, then that would imply that your screen is running at approximately 29 Hz.
I cannot think of any reason why my code would consistently measure 29 Hz when the display is actually 50 Hz (which it should be, if the CRTC is running at ~16 MHz, because I reprogram all the registers, which must result in ~50 Hz in that case).
And yes, I can definitely see 45 lines of text, 8 pixels high.
Is this fact so weird?
Well, in a way it is... Namely, a frame is 370 scanlines long in total, including vertical blank period. So if you have 360 visible lines, then either the CRTC doesn't actually do a full 16-scanline vertical blank... Or it doesn't disable the visible scanlines during the entire period. Which is a bit counter-intuitive, but it might be how it works.
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