Panelplayer User Manual v.1.4
Page 38
9.10 Control codes
The control codes are characters (they belong to the first 32 ASCII characters and cannot
be printed out) which define the kind of information contained in the pack following them.
The control codes used are those which appear on the following table.
Panelplayer initialises the transmission sequence when it receives the character
ENQ.
Mnemonic
Code
Description
STX
02H
Start TeXt. Beginning of transmission of reply pack.
ETX
03H
End TeXt. End of reply pack.
ENQ
05H
EnQuiry. Beginning of pack addressed to Panelplayer ( or #
for RS485).
ACK
06H
ACKnowledge. Beginning of reply pack: all OK!
LF
0AH
Line Feed. End of line code.
CR
0DH
Carriage Return.
NAK
15H
Not AcKnowledge. Beginning of pack with error code.
N.B. The codes are expressed in hexadecimal.
9.11 Address (ADD)
The address is a number that allows the system Master to establish communication with
one of the various modules connected to the same serial line.
The value of this address is defined in Panelplayer through a configuration file
config.txt
(par. 9.2).
IMPORTANT
:
when setting the address it is necessary to be careful to not define
more than one module with the same number, otherwise the communication becomes
confused and irregular and the data exchanged will no longer make sense.
The address can assume any value between
00H and 1FH
.
The address is expressed in ASCII characters and consists of
2
characters.
Note! BROADCAST Commands (CMAD=00)
Panelplayer processes commands received with a 00 address without providing a reply.
9.12 Command (CMD)
This is used to define the operation to be carried out (for example PLAY, reading the state
or setting of the volume). The commands are defined in ASCII characters and consists of
2
characters.
In the following sections of this chapter, we provide the list of commands and every detail
about each command.
