Denon DCM 390 Serial Protocol - Page 5

Revision1.40 Date 24.May.'07 DCM390 Serial Interface Specification 5 page of 40 2 Command format and answer format The DCM380X uses commands each of which consists of a data row (some commands no need PC) composed of command codes (CC) and parameter codes (PC). The host shall be designed to send block check characters (BCC) following ETX, with the data row enclosed in STX (text start: 0x02) and ETX (text termination: 0x03). The DCM380X shall complete command receive with correct BCC codes. Here are the formats. Commands STX (Start of TeXt) 0x02 CC (Command Code) Command code PC (Parameter Code) Number of parameters is defined for each command. ETX (End of Text) 0x03 BCC (Block Check Character) CC + PC0 + PC1 + PC2 + + PCn + ETX = XY (hex) Each of X and Y is 4 bit long, X, Y=0,1,2,3,4,5,6,7,8,9,A, B, C, D, E, F BCCH is an ASCII code converted from X (higher 4 bits of sum) and BCCL is converted from Y (lower 4 bit of sum). BCCH and BCCL are ASCII coded data. Answers STX (Start of TeXt) 0x02 RC (Reply Code) Reply code (=Command code) AC (Answer Code) Answer code PC (Parameter Code) Number of parameters is defined for each command. ETX (End of TeXt) 0x03 BCC (Block Check Character) CC + PC0 + PC1 + PC2 + + PCn + ETX = XY (hex) Each of X and Y is 4 bit long, X, Y=0,1,2,3,4,5,6,7,8,9,A, B, C, D, E, F BCCH is an ASCII code converted from X (higher 4 bits of sum) and BCCL is converted from Y (lower 4 bit of sum). BCCH and BCCL are ASCII coded data. D&M