Confirmed Signals

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Confirmed Signals

In General

It cannot be ruled out that an incoming signal gets lost on its way to the call controller. A common cause are send and receive buffers that overflow for various reasons. Even the successful transmission of a message via the CAN bus is highly probable but not 100% guaranteed.

Signals

For the following virtual inputs the security of the transmission is of special importance:

  • Basic 0Eh, Sub 0Bh (Fire service enable)
  • Basic 0Eh, Sub 0Ch (Fire service)
  • Basic 0Eh, Sub 17h (Case of fire)
  • Basic 12h, Sub 01h .. FEh (Fire detector)

These are called confirmed signals.

Method

The Input Panel Unit, which controls the confirmed signal, sends after each change of state of the input a virtual input signal to the call controller of the involved lifts.

The Call Controllers check after each incoming virtual input signal whether it is a confirmed signal. If that is the case they send a confirmation as virtual output signal. In the Byte 2 (Lift) only the bit of the lift assigned to the call controller is set. The remaining bytes are a copy of the received virtual input signal. A controller that subsumes several call controllers sets the appropriate bits in byte 2.

The Input Panel Unit repeats the sending of the virtual input signal at a two second rate, starting with the last change of state of the input, if the confirmation of various call controllers is not corresponding to the state of the input. In byte 2 there are only bits set that are not confirmed.

Examples

Group with 3 lifts and a fire switch at the second floor at node 22.

Successful Transmission

COB-ID: 0x496  Data: 0x01 0x11 0x02 0x07 0x17 0x0E
COB-ID: 0x400  Data: 0x01 0x11 0x02 0x01 0x17 0x0E
COB-ID: 0x401  Data: 0x01 0x11 0x02 0x06 0x17 0x0E

Distorted Transmission

COB-ID: 0x496  Data: 0x01 0x11 0x02 0x07 0x17 0x0E
COB-ID: 0x400  Data: 0x01 0x11 0x02 0x01 0x17 0x0E
... 2 Seconds ...
COB-ID: 0x496  Data: 0x01 0x11 0x02 0x06 0x17 0x0E
... 2 Seconds ...
COB-ID: 0x496  Data: 0x01 0x11 0x02 0x06 0x17 0x0E
COB-ID: 0x401  Data: 0x01 0x11 0x02 0x06 0x17 0x0E

Configuration

For the confirmed signals there is not configuration in the objects 6200h to 621Fh necessary.

Demarcation

The confirmed signals improve certainty that an input signal of a device reaches the control. The validity of the input signal itself is not verifiable with confirmed signal. Since this is available in the device it can be forwarded to the signal source if necessary.