I found this Assembler program that uses CTS and RTS:

http://www.ecomorder.com/techref/mic...tinttst-rh.htm

I kinda follow the code, sorta. At least I understand his note about how RTS and CTS have to be opposite since MAX232 will invert their value; so you set 0 to get 1 and vice versa.

I figure the same routine could be written in BASIC Pro, I'm just not sure on some of the variables and sizes (like for the input/output buffers, stuff like that).

So now I gotta tear at my MAX232 circuit, I had only used one line, leaving the other unused. I put it on a small board for the sake of convenience when moving it about my projects. Well, having no working room on it isn't proving convenient any more.

At least it's a start as to how to use USART with RTS and CTS. I can't find any references for the 'flow pin' used in SERIN2 so my options are getting slimmer.

Robert