Arcam MULTI ZONE POWER AMPLIFIER MZ8 - Manual (Page 13)

13
rs232 control
Conventions
All hexadecimal numbers begin 0x.
Any character in single quotes gives the ASCII equivalent of a hex value.
represents an unknown or variable number.
Command and response formats
Communication between the remote controller (RC) and the MZ8/MZ12 takes the form of sequences of bytes, with all commands and responses having
the same basic format. The MZ8/MZ12 shall always respond to a received command, but may also send messages at other times.
Each transmission by the RC is the following format:
St (Start transmission): 0x21 ‘!’
Zn (Zone number): see below.
Cc (Command code): the code for the command
Dl (Data length): the number of data items following this item, excluding the ETR
Data: the parameters for the command
Et (End transmission): 0x0D
Each response by the MZ8/MZ12 is the following format:
St (Start transmission): 0x21 ‘!’
Zn (Zone number): see below.
Cc (Command code): the code for the command
Ac (Answer code): see below.
Dl (Data Length): the number of data items following this item, excluding the ETR
Data: the parameters for the response of length n. n is limited to 255.
Et (End transmission): 0x0D
The MZ8/MZ12 responds to each command from the RC within three seconds. The RC may send further commands before a previous command
response has been received.
1
5
6
9
1
5
6
9
DB9 F
emale
DB9 F
emale
The cable is wired as a null modem:
Connector 1 pin Connector 2 pin Function
2 3 Rx  Tx
3 2 Tx  Rx
5 5 RS232 Ground
Data transfer format
• Transfer rate: 38,400bps.
• 1 start bit, 8 data bits, 1 stop bit, no parity, no flow control.
Serial Cable Specification
Introduction
This document describes the remote control protocol for controlling the MZ8/12 via the RS232 interface.
The document relates to MZ RS232 control protocol version 1.0. Any updates to this protocol will be posted on the Arcam Extranet website at
http://www.arcam.co.uk/extranet.