i want to use the RTS and CTS lines of the SR232 port with my PIC
i seam to be seeing thses two lines pointing in different directions in diffrent applications.
So for my PC to PIC communication, which way do each of these pins point to?
does the PIC send a RTS signal to the PC with the PC returning a CTS or is it the other way around?
i want to be able to stop the PC from sending any more data until i'm ready to receive and process them.
You can also use XON/XOFF flow control. When the pic has had enough it send a XOFF (0x13) character to stop the PC. Sending XON (0x11) will restart it.
When you have decided what to do and you feel the need for handshaking, I would go for CTS control rather than XON/XOFF.
Software control was OK for very slow baud rates, but it can cause overflow/overrun errors at higher baud rates.
I have a 32 byte fifo on the pic and send an XOFF when it contains 28 bytes and an XON at 20 bytes. This is completely transparent to the main process.