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9.3 " Framing" error on the master
When commercial RS-485 interfaces are used on the master, a Framing error may take
place if nothing is being transmitted on the serial line.
In order to avoid this mishap, it is indispensable that the system master ignores all the data
until it has received one of the STX, ACK or NAK characters coming from a Panelplayer.
9.4 NAK reply by Panelplayer
The reply with the character NAK is sent from Panelplayer to the master when any kind of
error is detected in the message received.
9.5 Transmitting a command by master
When you send a command from the master to Panelplayer using one of the dedicated
protocols, make sure you send it with a delay of at least 10mS starting from the moment
the last command received by Panelplayer has been completely performed.
IMPORTANT:
remember to bear in mind or to ignore the echo of the command that is sent from the
master (with RS485 an echo is always present).
9.6 How to read the figures of the dedicated protocols
When the master reads the data from Panelplayer.
(Panelplayer > Master)
Panelplay
The data areas A and C indicate the transmission of data from the master to
a)
Panelplayer.
The data area B indicates the transmission of data from Panelplayer to the master.
b)
The programme of the Master is structured so as to manage the data in the manner
c)
shown on the figure from left to right. Therefore, the data management sequence is A, B,
C.
In area A, the character ENQ (05
Example :
indicated as "
Data
Panelplayer User Manual v.1.4
when one is using the RS485 bus (only on a duplex cable)
A
E
N
Data
Master
Q
" in the figure to the right of the character ENQ.
C
A
C
Data
K
S
T
Data
X
B
) is transmitted, followed by all the other data
H
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