This file/pin mode is designed to drive a VGA monitor RGB and H and V Sync lines. The output is essentially 1 bit, with the ability to change the color between 8 colors (including black) by horizonal line.
This pin mode is unusual among SW18AB pin modes because it requires specific pins to be used for certain things. Pins must be:
\warn This pin mode stretches the limits of what the SW18AB chip can do while still being able to do other things - some flicker / jitter is to be expected
The rate at which the display can be updated is slower than with a hardware connected LCD or OLED. The Serial Wombat protocol's 8 byte in / 8 byte out packet structure is not ideal for moving large blocks of data such as screen pixel data. This mode is better suited to data displays than real-time games, for example.
The pin mode is capable of limited color generation with the restriction that an entire horizontal line must be the same color. Colors are achieved by turning Red, Green, and Blue lines totally on or off in combinations.
This pin mode implements a 160x120 pixel output to a monitor in 640x480 mode with black bars around part of the screen. This was the best I could do using the chip's SPI in DMA mode.
The SerialWombat18ABVGADriver class (A separate Arduino Library) is designed to act as a wrapper between this pin mode and the AdafruitGFX library. See the Arduino examples for this pin mode for an example.
This pin mode uses a significant amount of SW18AB time that is not measured using typical methods due to the high number of interrupts it produces. These interrupts happen both during and outside of the main loop executive processing, so actual system utilization is higher than normal metrics indicate.