Lika SMAX-AI1-PRG-L2, Руководство пользователя

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SMAX MODBUS®
value 1 next to the Serial com baud rate [0005 hex] parameter (register 6)
from the Slave having the node address 1 previously and the node address 10
currently is as follows:
Response PDU
(in hexadecimal notation)
[0A][10][00][04][00][02][01][72]
where:
[0A] = new Slave address
[10] =
16 Write Multiple Registers
function code
[00][04] = starting address ( Node address [0004 hex] parameter, register 5)
[00][02] = number of written registers
[01][72] = CRC
WARNING
For safety reasons, when the encoder is on, a continuous data exchange
between the Master and the Slave has to be planned in order to be sure that the
communication is always active; this is intended to prevent danger situations
from arising in case of failures in the communication network.
For this purpose the Watchdog function is implemented and can be activated as
optional. Watchdog function is a safety timer that uses a time-out to detect
loop or deadlock conditions. For instance, should the serial communication be
cut off while a command is still active and running Watchdog safety system
immediately takes action and commands an alarm to be triggered. To enable the
Watchdog function, set to “=1” the
Watchdog enable
bit 0 in the
Control
Word [000A hex]
variable. If “=0” is set the Watchdog is disabled; if “=1” is set
the Watchdog is enabled. When the Watchdog function is enabled, if the device
does not receive a message from the Server within 1 second, the system forces
an alarm condition (the
Watchdog
alarm message is invoked to appear as soon
as the Modbus network communication is restored).
MAN SMAX MB E 1.2 Modbus® interface 58 of 84