Which products are affected?
8200 vector/motec with field bus function module system bus CAN E82ZAFCCxxx
How is the reaction?
If a reset node telegram is sent via the CAN bus or the CAN controller is disconnected from and reconnected to the mains, all connected CAN devices are reinitialised. Then, the CAN controllers (slaves) remain in the pre-operational state. In this state, a process data communication (PDO) is not possible. The slaves can now use 'previous values' of the input buffer of the CAN controller. A network telegram 'Go from pre-operational to operational' of the master only sets all devices to operational and the PDO communication is possible.
Input word state after a reset node:
CAN-IN1: W1 + W2 = zero, W3 +W4 = old values
CAN-IN2: W1 + W2 = zero, W3 +W4 = old values
When does the problem occur?
When the words 3 + 4 of CAN-IN 1 or CAN-IN2 are used.
Possible diagnostics?
This malfunction is possible if the controller carries out undefined functions in the 'pre-operational' state.
Short-term measures/recommendations?
Control and setpoint input via CAN-IN1/2 word1 and word2
Evaluation
The undefined state of the input buffer in the CAN state 'pre-operational' of the controller can cause malfunctions of the device. As soon as the PDO communication is active - CAN state 'operational' - the previous values in the input buffer are overwritten by new ones.
