Hello,
My problem statement is something like this:
- Implement a Transmit Enable (TxEn) on a GPIO pin.
- TxEn should be initialized low.
- TxEn should be pulled high 30us before the first start bit transmission begins.
- TxEn should remain high during serial transmission of multiple bytes.
- TxEn should be pulled low 60us after the last stop is transmitted.
- TxEn handling and serial transmission should not substantially block main program execution.
I figured I need to use the GPIOTE and PPI functionality.
My question is that since I have 3 functions to take care of: GPIO transition, timer compare and UART start/stop, how best can I utilize GPIOTE and PPI to accomplish this.
Option 1: Event - GPIO low to high, Task- timer compare and then start UART
Option 2: Set GPIO high, Event - Timer compare, Task- UART start
What approach should I follow? Is there another option, is there a way to use all 3 in a GPIOTE-PPI combination?
Thanks