Harman Kardon SIG2.0 Owners Manual - Page 18

SIGNATURE BUS PROTOCOL MASTER DOCUMENT Revised 2-24-98 SOFTWARE REVISION LEVEL REQUEST COMMAND: Preamble Target Byte Device Type Target Unit ID Source Device Type Source Unit ID Data Length Command Modifier Command Byte Data Byte(s) 7Eh 20h 01h 30h 01h Computed 01h 77h None Checksum Byte See page 7 RESPONSE: Preamble Target Byte Device Type 7Eh 30h Target Unit ID 01h Source Device Type 20h Source Unit ID 01h Data Length Computed Command Modifier 02h Command Byte 77h Data Byte(s) Checksum Byte See below See page 7 The Software Revision Level Request command causes the target unit to transmit, in the response, the revision level of its software. The response is a data word organized as follows: MSB Major revision level LSB Minor revision level Example: 0205h would be software version 2.5 DB-25 1 2 3 4 5 6 DCE TXD RXD RTS CTS DSR DB-9 3 2 7 8 6 AA x BA I BB O CA I CB O CC O Protective Ground Transmitted Data Received Data Request To Send Clear To Send Data Set Ready Page 18 of 20