Microchip Graphics Library


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I am using the 256 x 64 OLED screen model CFAL25664A-Y-B1 which uses STV8105 controller on the eval board DMO-L25664AYB1. The STV8105 is not currently supported by the microchip graphics library, has anyone else used this screen? What graphics library did they use?

The problem with the STV8105 is it's not pixel addressable. Since it's a 4bit screen, it uses it's 8bit bus (parallel or SPI) to address 2 row pixels at a time. That is, there are 256 pixels (0 thru 255), first two pixels are address 0. Data at address 0: Pixel 0 is full ON at 0x0F (LSNibble), and pixel 1 is ON at 0xF0 (MSNibble). Both are on at 0xFF. This proves to be troublesome for a library which is trying to draw single dots to show, for example, a circle.

For single pixel drawing, I'm trying to avoid a Read-Modify-Write situation to read the other pixel.

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Since the display is "write only", you won't have to worry about doing a Read-Modify-Write. I'm thinking your best solution is to have a virtual image of the display content in your cpu ram, and do all your drawing in memory, then update to the display. That would require 8K of ram.