Table of Contents
Advertisement
User Manual
2
Software
The software consists of two parts which com-
municate across the parallel printer port of the
PC. One part is executed by the microproces-
sor inside CPC-PP and can not be changed by
the user. The application program runs on the
PC and makes use of the interface library.
2.1 Functions of CPC-PP
CPC-PP offers enhanced functionality for CAN
communication:
Transmission and reception of
•
CAN-messages
Filtering and buffering of received mes-
•
sages
Measurement of bus-load
•
The functions of CPC-PP are accessed across
the interface library of the PC.
2.2 Application program: Realization concepts
The library of interface functions supports two
ways to implement the application program.
The synchronous mode complies with conven-
tional programming. The sequence of program
steps is given by the program structure. Asyn-
chronous mode allows event driven program-
ming similar to the way used in graphical user
interfaces.
EMS Dr. Thomas Wünsche
CPC-PP
3
CPC-PP
2.3 Synchronous Interface
The implementation of the
main program with synchro-
main
nous interface allows simple
program
and clearly arranged pro-
grams with sequential flow. It
command
is suitable mainly for simple
initiation
applications, which allow a
command
predefinition of events to pro-
execution
wait for result
cess. This is true if, for exam-
by CPC-PP
ple, only CAN-messages are
continue
to be received or only
bus-load measurement is to
be realized.
2.4 Asynchronous Interface
The asynchronous interface
provides enhanced flexibility
in reaction to events which
are not predictable in their
sequence of occurrence.
main
Communication objects can
program
be processed independently
of program state, reactions
command
initiation
can be configured flexible.
command
further
execution
program
For this purpose every com-
by CPC-PP
execution
munication object is handed
use result
on to a set of handling
functions. Such functions are
provided within the program-
ming library. The application
programmer can add routi-
nes as required by applicati-
on purposes.
4
EMS Dr. Thomas Wünsche
User Manual
Advertisement
Table of Contents
