Direct access to graphics frame buffer

Posted on Wed 26th, August 2020

• #1

user113695

Hi,
Is the graphics frame buffer on the Bangle memory-mapped and accessible from within JS? Or is data transferred in chunks to the LCD controller via SPI?
Thanks,
Marko
• #2

fanoush

There are both modes available. Memory mapped one has lower resolution due to high memory requirements. Default full size one is unbuffered - data is transferred to LCD when drawing however it is not over SPI, there is 8bit parallel bus. See https://banglejs.com/reference#l_Bangle_setLCDMode
• #3

Gordon

The display itself is connected by an 8 bit parallel bus (not memory-mapped) - but it is write-only so the memory is only really useful for graphics.

As @fanoush says there are other graphics modes provided though that do use a lower resolution offscreen buffer stored in RAM.

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