>Yeah, I thought that might be the case. I tried a crossover from COM1: to COM2: and ran 2 instances of Procomm. Also took a single port over to an Epson LQ-850 in Hex Dump mode. In all cases, all I see is hex(01 41 0D) for his F2 sequence. All function keys in Wyse-50 emulation exhibit the exact same behavior in Procomm. I am beginning to think these default function keys are meant to be terminal to host only, not to drive the terminal.

Seems odd that Fopen/Fwrite work though.
Have you tried other Wyse-50 sequences - see this site

http://www.nw.com/nw/WWW/products/wizcon/wyse50.html