PCAN-USB – User Manual
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5.2.2
Principle Description of the API
The PCAN-Basic API is the interface between the user application
and device driver. In Windows operating systems this is a DLL
(Dynamic Link Library).
The sequence of accessing the CAN interface is divided into three
phases:
1.
Initialization
2.
Interaction
3.
Completion
Initialization
A CAN channel must be initialized before using it. This is done by
the simple call of the function
CAN_Initialize
. Depending on the
type of the CAN hardware, up to eight CAN channels can be opened
at the same time. After a successful initialization the CAN channel is
ready for communication with the CAN hardware and the CAN bus.
No further configuration steps are required.
Interaction
For receiving and transmitting CAN messages the functions
CAN_Read
and
CAN_Write
are available. Additional settings can be
made, e.g. setting up message filters to confine to specific CAN IDs
or setting the CAN controller to listen-only mode.
When receiving CAN messages, events are used for an automatic
notification of an application (client). This offers the following
advantages:
The application no longer needs to check for received messages
periodically (no polling).
The response time at reception is reduced.
