http://www.openhacks.com/uploadsproductos/at137139_tcpip_appnote.pdf

AT137 AT command manual

Change Baud Rate from 115200 to 9600

1. Start-> Accessories-> Communication-> Hyperterminal
2. Open new connection
3. “Connect using:” the correct COM port, you will see a
windows->change Bits per second to “115200”
4. Type “ATE1” and press Enter (it’ll show “ok”)
5. Type “AT+IPR=9600” and press Enter (it’ll show “ok”)
6. Click on “disconnect” icon
7. Go to Properties and change the Bits per second to “9600”
8. type “AT&W” and press Enter (it’ll show “ok”)

Then it’ll be changed to 9600.