> >This doesn't agree with my experience. I have used Hyperterm > >many times to talk to simple devices that use only RX, TX, and > >GND without any handshaking loopback. Hyperterm definitely > >does not send anything to the device on startup, only when a key > >is pressed. > > It does not send a character on the TX line, but it does play with the > DTR/DSR lines to detect if there is a device it can talk to. The hardware handshaking is likely a requirement of your hardware, not of Hyperterm. [That's not to defend Hyperterm, which in my experience is about as reliable and easy to work with as a politician.] Aza D. Oberman -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist