How to factory reset the GL8200 modem? I can’t use AT commands because of an incorrect value used with AT+IPR command (AT+IPR=6000000).
So just to be clear you have accidentally set the baud rate on the serial port to 600K and can no longer interface to it. You now want to be able to set the unit back to its default of 115200bps so that you can re establish communications? If this is the case then there is no way to do it, there is a single hardware interface which controls the unit, if this is set to something that you can use then thats it.
You need to find a way to connect to it at 600kbps, I would suggest buying a USB to serial converter which is capable of this speed and using the cable that comes with the GL to reset it back via a PC/terminal program.