Really?

https://www.abbreviations.com/RTS

I assumed you knew I was talking about serial communication. AND! it was only my opinion. As Mr Chips quite clearly said without the bulk we're guessing, BUT! the code for semaphore SPI on stack overflow kinda bolsters my suspicions.

 

My 2 peneth..

Semaphore is a flag.. Used to be used on ships to relay information to other boats. RTS has always been "Ready To Send"

Semaphore Ready To Send set flag up, down or toggle condition.. t even has its own SRTS status byte..

Thank you Ian Rogers.

 

WBahn,
Thank you for your answer.
I will try and start over again.