I am working on an LCD CLI, that runs completely separate from the main interface (events and Hdmi). It's purpose is to provide a control interface for the pi (power, volume, crashed Kodi recovery, etc)
Currently from C, I am using wiringPi and the bcm2835 libraries for GPIO control, feeding the ILI9469l, and reading the XPT2046..
Being a mostly static display, I have it running from interrupts and init, only running the program when actually needed.
However, for touch events, the program gets ran 50+ times, reading the touch location, and updating the display accordingly. This leads to a lot of Un needed overhead, loading the wiringPi and bcm2835 libraries each time.
What is the minimal code needed to send and receive 3 bytes from a 4wire spi interface? I have tried the minimal_spi approach, but it hangs on waiting for SPI_TXD and SPI_CS_DONE.. Is this documented anywhere?
Also, outside of WiringPi, I have not been able to read or write GPIOs reliably..
I may have the variable names wrong, I am at work, and do not have the code in front of me.