user manual
Grandstream Networks, Inc.  GXP21xx User Manual  Page 19 of 41 
                 Firmware version: 1.0.1.66         Last Updated: 05/2011 
CALL FEATURES 
The GXP21xx supports traditional and advanced telephony features including caller ID, caller ID w/name, 
call forward/transfer/park/hold as well as intercom/paging and BLF.  
Table 11: GXP21xx Call Features  
Key  Call Features 
*30  Block Caller ID (for all subsequent calls) 
*31  Send Caller ID (for all subsequent calls) 
*67  Block Caller ID (per call) 
*82  Send Caller ID (per call) 
*70  Disable Call Waiting (per Call) 
*71  Enable Call Waiting (per Call) 
*72  Unconditional Call Forward  
Dial “*72” for a dial tone. Dial the forwarding number followed by “#”. Wait for dial 
tone. LCD will display “Call FWD Activated”. 
*73  Cancel Unconditional Call Forward: dial “*73” and get the dial tone, then hang up. 
LCD will display “Call FWD Activated”. 
*90  Busy Call Forward 
Dial “*90” for a dial tone. Dial the forwarding number followed by “#”. Wait for a dial 
tone. Hang up. 
*91  Cancel Busy Call Forward: dial “*91”. Wait for dial tone. Hang up. 
*92  Delayed Call Forward 
Dial “*92” for a dial tone. Dial the forwarding number followed by “#”. Wait for a dial 
tone. Hang up. LCD will display “Call FWD Activated”. 
*93  Cancel Delayed Call Forward 
Dial “*93” for a dial tone, then hang up. 
CUSTOMIZED LCD SCREEN & XML 
Grandstream GXP21xx Enterprise IP phone support both simple and advanced XML applications: 1) XML Custom 
Screen, 2) XML Downloadable Phonebook and 3) Advanced XML Survey Application. For more information on 
how to create a downloadable XML phonebook, creating a custom idle screen and/or reprogramming the soft-keys 
on GXP21xx, please visit our website at: 
http://www.grandstream.com/support 










