Cannot receive extended CAN messenges

[power-max]

No extended CAN messages will come through even when the relevant fields are set. The pawelsky library is more usable in this regard.

[Kython89]

By default the filter initializes such that it filters out extended frames. This solved my problems.
CAN_filter_t filter;
filter.flags.extended = 1;
Can0.begin(500000, filter);