NEC E437Q External Controls - Page 30

10. Get Timing Report 10.1 Get Timing Report and Timing reply. The controller requests the monitor to report the displayed image timing. 1) The controller requests the monitor to get timing report. Header SOH-'0'-Monitor ID'0'-'A'-'0'-'4' Message STX-'0'-'7'-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 status. Ex.) If Monitor ID is '1', specify 'A'. '0' (30h): Message sender is the controller. 'A' (41h): Message Type is "Command". '0'-'4' (30h, 34h): Message length is 4 bytes. Message STX (02h): Start of Message '0'-'7' (30h, 37h): Get Timing Report command. 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 Complete "Get Timing Report" command packet as follows; ASCII: 01h-30h-41h-30h-41h-30h-34h-02h-30h-37h-03h-CHK-0Dh SOH-'0'-'A'-'0'-'A'-'0'-'4'-STX-'0'-'7'-ETX-CHK-CR 2) The monitor replies Timing report to the controller. Header Message SOH-'0'-'0'-Monitor ID'B'-'0'-'E' STX-'4'-'E'-SS-H Freq-V Freq-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'. 'B' (42h): Message type is "Command reply". '0'-'E'(30h, 45h): Message length Message STX (02h): Start of Message '4'-'E' (34h, 45h): Timing reply command SS: Timing status byte Bit 7 = 1: Sync Frequency is out of range. Bit 6 = 1: Unstable count Bit 5-2 Reserved (Don't care) Bit 1 1: Positive Horizontal sync polarity 0: Negative Horizontal sync polarity. Bit 0 1: Positive Vertical sync polarity. 0: Negative Vertical sync polarity. (30/47)