An isolation issue?

[SCOTTIE]

Well, the opto-isolator really works. This isolator works perfectly with my laptop(IBM T42, using an extra rs232-usb converter to my usb slot). However, I also found something weird. When I switch everything to another laptop(DELL D600), that laptop can't receive pH readings in the LabVIEW program from the pH meter no matter rs232 or usb interface I connect to. What the program could read is only unmeaningful characters. Does anyone know why it acts like this? Here is its datasheet:

https://www.quatech.com/pdf/9spop2.pdf

From the datasheet, this isolator is supposed to receive and transmit data from both directions. Do I need to reverse the isolator as it mentioned in the datasheet? WOW, have to buy two db9 gender changers. Thanks for anyone's opinion.



Scottie

[AnalogKid2DigitalMan]

Are you programatically setting up the port for proper baud, duplex, stop but, parity, handshaking, etc in your LV code?
If not, then could be that default port settings are different between computers.
Have you verified proper communication in Hyperterminal?