Upper Electronic Module
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The upper electronic module (4/70) transmits information via the Control area network (CAN) to the central electronic module, about which button on the remote control is depressed and the status of the siren.
The central electronic module in turn sends information to the upper electronic module via the Controller area network (CAN), if the siren must be activated. The upper electronic module transmits information via serial communication (Volcano Lite) to the siren control module, which activates the siren.