WAGO-I/O-SYSTEM 750
Function Description 35
750-658 CAN Gateway
Manual
Version 1.2.1, valid from FW/HW-Version 01/01
5.2
Filter Settings
With 6 configurable pass-through filters, the bandwidth of the CAN telegrams for
the user transmitted to the controller can be limited to specific ranges. This saves
resources on the control level and in the I/O module.
A CAN ID can be specified for the upper and lower limits per filter. The value of
the upper limit must be greater than or equal to the value of the lower limit.
Otherwise, the I/O module will output an error message. Only the telegrams are
transmitted that fall within the filter limits.
Transmission of CAN telegrams from the I/O module to the controller can take
more time than receiving these telegrams on the CAN bus. Thus, several CAN
telegram of the same CAN ID may be cached in the I/O module. The following
settings can be made:
1.
"Overwrite"
2.
"Keep All"
5.2.1
"Overwrite" Setting
If this setting is selected, newly received telegrams are overwritten when
telegrams of the same CAN ID are received. This requires that the received
telegram has not yet been forwarded to the controller. The system workload can
be reduced significantly.
Do not select "Overwrite" for protocol data!
The "Overwrite" setting should not be selected when protocol data of higher
layers (e.g. SDOs, etc.) is transmitted. It may be unusable because all data of a
CAN ID is required in general. Select the "Keep All" setting here.
5.2.2
"Keep All" Setting
If this setting is selected, received telegrams are not overwritten, rather forwarded
to the controller sequentially. Only use this setting when data usage of received
CAN telegrams is low.