Using XT09-PKI-R with a serial to USB converter


I am trying to use a XT09-PKI-R with a Prolific PL2303 serial-USB converter on the laptop side. My setup is as follows:

Laptop -> PL2303 -> XT09 ~ Wireless ~ XT09 -> Actuator

The X-CTU software recognizes the COM port for the Prolific device. It shows up in PC Settings > Com Port Setup as ‘Prolific USB-to-serial Comm. (COM4)’. Other settings are unchanged from default: Baud 9600 … Flow Control NONE … Data Bits 8 … Parity NONE … Stop Bits 1.

However, when I do a Test/Query for this setup, I get an error message window : Unable to communicate with modem.

I have to use the serial-USB since I don’t have a serial port on my laptop. I wanted to check if someone else on this forum has had a similar problem and how it could be resolved.


are you sure the baud rate on the modem you are trying to connect to is set to 9600? confirm the modem config.

I use a USB to Serial cable with no issues.

Thank you, you were right that the modem was not set to the correct baud rate. For the benefit of others who might be facing the same issue, I had to go to X-CTU > Modem Configuration, select the right modem from the drop-down list, and set the correct baud rate. Then, I did a Write to the modem and the new configuration was established.

However, I still am facing an issue with the setup. Once the modems are set up, can I simply send my serial commands through a C++ program which was earlier working with a wired connection? That is:

Earlier: PC —command—> USB to serial -> Actuator
Now: PC —command—> USB to serial ->XT-09 ~ Wireless ~ XT-09 -> Actuator

are both equivalent? Or do I need to have my C++ program set up differently to account for the serial wireless link?

Thanks again for your help!