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10 CVG-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: Y Control_Type Function Param CR
Reply
: Z Control_Type Function Param CRDone>CR
Get
Command: Y Control_Type Function Param CR
Reply
: Z Control_Type Function Param CR
Example:
1. "Y 1 17 0-127 CR" -> set Contrast value. (4th byte is between 0 and
127).
"Z 1 17 0-127 CR>" --> Reply value
"DoneCR" --> command setting success
2. "Y 4 21 0-17 CR" -> get current output resolution. (4th byte is
between 0 and 17).
"Z 4 21 0-17 CR>" -> Reply value
3. "Y 0 35 CR" -> Volume down. Each time we apply this command will
decrease the volume level by one step.
"Z 0 35 CR>"-->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"
