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KeepIS

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Joined: 13/10/2014
Location: Australia
Posts: 1945

Posted: 09:09am 19 Feb 2019

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I've had a search but came up empty. I'm using blit to read / restore an image on "part" of the and 8" display on an ArmMite H7.

Everything works as expected but of course I get flashing of the updated triangle pointer positions using blit write, not all the time, I can get 4 or 5 blit write updates restoring the previous background with no flashing before I get 3 or 4 updates with flashes and so on repeating.

I assume it's to do with not writing to the display at the correct scan time, so my Questions are:

1: Am I on the right track?
2: Is there a way to detect the scan position on the H7?

I can't use refresh as the 8" screen in buffer mode only leaves 96K of ram for blitz copy.

Mike.Edited by KeepIS 2019-02-20

NANO Inverter: Full download - Only Hex Ver 8.1Ks

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10572

Posted: 09:57am 19 Feb 2019

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There is a function that I hadn't previously implemented to help with this.

getscanline()

This return the current line that is being written to by the display controller. By a process of trial and error you can use this to delay writes until the display cursor is "out-of-the-way"

Included in this version (very very limited testing)

2019-02-19_195727_Armmite1.3.zip

example use:

i=getscanline()
do while i>400 or i<= mm.fontheight
i=getscanline()
loop
text 0,0,TIME$

This is also implemented in the MM+ and MMX but doesn't seem to appear in the MM+ manualEdited by matherp 2019-02-20

KeepIS

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Joined: 13/10/2014
Location: Australia
Posts: 1945

Posted: 02:29am 20 Feb 2019

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Once again, thank you for the quick reply, exactly what I wanted.

Using getscanline() I now have "blit write" running with no flashing, it took a while to get the sweet spot though.

I now have a beautiful big clock running on half the 8" screen, now I can add lots of alarm times, spoken messages/music/chimes, calendar reminders and more. Auto backlight makes it great at night, with an 8" screen you can read the clock from across the room at a glance. Thanks again.

Mike.

NANO Inverter: Full download - Only Hex Ver 8.1Ks

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