NEC E657Q External Control Codes - Page 20

IV. Control Commands 6. Typical procedure example The following is a sample of procedures to control the monitor, these are examples of "Get parameter" and "Set parameter". 6.1. How to change the "Backlight" setting. Step 1. The controller requests the Monitor to reply with the current brightness setting and capability to support this operation. (Get parameter) Header SOH-'0'-Monitor ID- '0'-'C'-'0'-'6' Message STX-'0'-'0'-'1'-'0'-ETX Check code BCC Delimiter CR Header SOH (01h): Start of Header '0' (30h): Reserved Monitor ID: Specify the Monitor ID from which you want to get a value. Ex.) If Monitor ID is '1', specify 'A'. '0' (30h): Message sender is the controller. 'C' (43h): Message type is "Get parameter command". '0'-'6' (30h, 36h): Message length is 6 bytes. Message STX (02h): Start of Message '0'-'0' (30h, 30h): Operation code page number is 0. '1'-'0' (31h, 30h): Operation code is 10h (in the OP code page 0). ETX (03h): End of Message Check code BCC: Block Check Code Refer to the section 4.3 "Check code" for a BCC calculation. Delimiter CR (0Dh): End of packet Step 2. The monitor replies with current Backlight setting and capability to support this operation. Header SOH-'0'-'0'-Monitor ID'D'-'1'-'2' Message STX-'0'-'0'-'0'-'0'-'1'-'0'-'0'-'0' -'0'-'0'-'6'-'4'-'0'-'0'-'3'-'2'-ETX Check code BCC Delimiter CR Header SOH (01h): Start of Header '0' (30h): Reserved '0' (30h): Message receiver is the controller. Monitor ID: Indicate a replying Monitor ID. Ex.) When this byte is set to 'A', the replying Monitor ID is '1'. 'D' (44h): Message Type is "Get parameter reply". '1'-'2' (31h, 32h): Message length is 18 bytes. Message STX (02h): Start of Message '0'-'0' (30h, 30h): Result code. No error. '0'-'0' (30h, 30h): Operation code page number is 0. '1'-'0' (31h, 30h): Operation code is 10h (in the page 0). '0'-'0' (30h, 30h): This operation is "Set parameter" type. '0'-'0'-'6'-'4' (30h, 30h, 36h, 34h): Backlight max value is 100(0064h). '0'-'0'-'3'-'2' (30h, 30h, 33h, 32h): Current Backlight setting is 50(0032h). ETX (03h): End of Message (20/47)