Control Codes; Address (Add); Command (Cmd) - inout Panelplayer User Manual

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
STX
ETX 03H
ENQ 05H
ACK 06H
LF 0AH
CR 0DH
NAK 15H
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:
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.
Panelplayer User Manual v.1.4
Description
Start TeXt. Beginning of transmission of reply pack.
02H
End TeXt. End of reply pack.
EnQuiry. Beginning of pack addressed to Panelplayer ( or #
for RS485).
ACKnowledge. Beginning of reply pack: all OK!
Line Feed. End of line code.
Carriage Return.
Not AcKnowledge. Beginning of pack with error code.
when setting the address it is necessary to be careful to not define
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