ICP DAS USA I-7521 User Manual page 141

Application 9: Real time Analog Signal Monitoring and Alarm
 Refer to Applications 1 and 2 for more information
 COM1 of the Host PC is used as the Host RS-485 network. The Host PC
will send commands and receive responses through the RS-485
network
 COM2 of the Host PC is used as an emergency RS-485 network. All
I-7522 modules will automatically monitor the analog signal connected
to an HP34401A. If an emergency event occurs, the I-7522 module will
send an emergency command to this RS485 network. If multiple I-7522
modules send emergency commands to the Host PC at the same time,
the I-7522 modules will continue to send emergency commands to the
Host PC until confirmation is received from the Host PC
 All analysis operations are performed in the I-7522 module. The Host
PC only reads the analog values as part of its system monitoring
function
 Refer to the 7522ODM5.c file for the source code of the firmware
COM2
I-7520
I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527 User's Manual,Ver2.5 Aug.2015
Control (Master type)
RS-232 I-7520
COM1
COM2
RS-232
COM1
I-7522
COM3
Emergency RS-485 Network
Host RS-485 Network
(#01)
HP34401A
COM2
COM1
I-7522
COM3
(#AA)
HP34401A
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