I have HP EliteBook 8570p Notebook
The serial port on the laptop has a problem , when i connect any device to configure it on that serial port , the messages that have been output from the device appears normally , but when i tried to write anything via my keyboard it does not response to any key of keyboard , so the com port can read but cannot write.
1. i installed windows again , the same problem.
2. i used another software differ from hyper terminal , such like Tera term , putty , and the same.
3. i tried many routers , switches from different vendors to see if the problem from the device not the serial port of laptop , but the same
4. i've updated the bios and all the drivers to latest version , and the same.