Greetings everyone,

first of all, thank you so much for your help.
Will try your suggestions tonight and give feedback.

@Richard, just to explain...the red bits are there only to trigger the IOC on the receiver side so that it knows when it needs to start listening.
The reason is because the receiver PIC will do a lot of tasks and will only stop to pay attention to the RX pin when the IOC is triggered.
The IOC and RX pins are defined as the same pin to save an I/O pin on both sender and received PICs.


Best regards
Rui