User manual
VP-724xl Communication Protocol 
47
10  VP-724xl Communication Protocol 
This protocol includes two types of commands: 3 bytes and 4 bytes. 
In the 3 bytes command type, the scaler operates in a fast mode because it does 
not save the information immediately. The sent command is executed 
immediately, but the status of the scaler is saved in the non-volatile memory only 
after 30 sec of no activity. 
In the 4 bytes command type, the scaler executes the save process immediately 
after each command. This operation consumes more time (adding about 2 sec). 
Set and Get command: 
Set Command: YControl_TypeFunctionParamCR 
 Reply: ZControl_TypeFunctionParamCRDone>CR 
Get Command: YControl_TypeFunctionParamCR 
Reply: ZControl_TypeFunctionParamCR 
Example: 
1.  "Y 1170-127CR" -> set Contrast value. (4th byte is between 0 and 
127). 
"Z1170-127CR>" --> Reply value 
"DoneCR" --> command setting success 
2.  "Y4210-17CR" -> get current output resolution. (4th byte is 
between 0 and 17). 
"Z4210-17CR>" -> Reply value 
3.  "Y035CR" -> Volume down. Each time we apply this command will 
decrease the volume level by one step. 
"Z035CR>"-->Reply value 
"DoneCR" --> command setting success 
Definition: 
: ASCII Code 0x20 
CR: Ascii Code 0xD or 0xA 
After set type Command setting, system will respond a string as "Done" 










