Is cable connection direct or null-modem?
Everything depends on your device cutoff point. Usually it is necessary to use null-modem cable, in which signals are moved apart in this way: Device | Computer _____________ RXD <--> TXD TXD <--> RXD GND <--> GND if device uses special signals DTR and others and you don’t want to use hardware data transmit control, at device side connect 7 and 8 contacts of DB9 cutoff point or analogous DB25 cutoff point signals. More hardware tips and articles you can found on our site http://www.aggsoft.com.
