SIGNATURE
B
US
P
ROTOCOL
M
ASTER
D
OCUMENT
Revised 2-24-98
Page 5 of 20
P
ROTOCOL
F
ORMAT
Note:
the symbols “
b
”, “
d
”, and “
h
” used in this document denote binary, decimal, and hexadecimal values,
respectively. All transmissions must be in hexadecimal.
The Preamble is a byte used to alert the system that a message is about to
be transmitted. This allows the system to ignore random noise, and
reliably receive valid messages. The Preamble is always equal to 7E
h
.
NOTE:
No other byte in any part of the message may equal 7E
h
.
The Target Device Type is a byte that distinguishes what type of unit the
message is intended for (i.e. a preamp versus a CD player).
HEX
Device Type
01
Audioaccess KPS keypad
04
Audioaccess Computer
05
Audioaccess Paging/SMM Module
06
Audioaccess PX-603
07
Audioaccess Internal Multi
20
Signature 2.0 Processor/Tuner
30
Signature 3.0 DVD player
50
Citation 5.0 AV Controller
70
Citation 7.0 AV Controller
99
Broadcast Message (everyone listens)
Source
Device Type
Target
Device Type
Target
Unit ID
Source
Unit ID
Command
Modifier
Data
Length
Preamble
Byte
Command
Byte
Data
Byte(s)
Checksum
Byte
Source
Device Type
Target
Device Type
Target
Unit ID
Source
Unit ID
Command
Modifier
Data
Length
Preamble
Byte
Command
Byte
Data
Byte(s)
Checksum
Byte
The Target Unit ID is a byte that distinguishes which unit of a given type
the message is intended for (i.e. CD player #1 versus CD player #2). The
Unit ID is set in the menu system of the unit you are trying to control,
default = 01
h.
If you are using more than one of any given unit, you will
need to modify this byte to reflect the ID number of the unit you are trying
to control.
Source
Device Type
Target
Device Type
Target
Unit ID
Source
Unit ID
Command
Modifier
Data
Length
Preamble
Byte
Command
Byte
Data
Byte(s)
Checksum
Byte
The Source Device Type is a byte that distinguishes what type of unit the
message is coming from (i.e. a preamp versus a CD player).
See above
list.
Source
Device Type
Target
Device Type
Target
Unit ID
Source
Unit ID
Command
Modifier
Data
Length
Preamble
Byte
Command
Byte
Data
Byte(s)
Checksum
Byte
