Module priority 

The priorities J1939 conventionally assigns.

A priority is three bits, 0 highest and 7 lowest. The standard leaves the choice to the application, but publishes these as the usual ones, so naming them keeps a bare number out of a call site.

Constants

CONTROL

The priority a control message such as engine speed is normally sent at.

DEFAULT

The default for everything that is not time critical, including requests.

LOWEST

The lowest priority, for traffic that may wait behind anything else.