CANopen Field Bus
80
Operating Manual XCx 300 / 500 / 540 Version 09/08
7.2.3
Access to network variables and I/O configuration
Network variables, function codes and parameters of parameterizing
and diagnosis functions are mapped to PLC addresses with the help
of the I/O configuration, and provided with symbolic names in the
variable declaration.
User-specific adaptation of the CANIO driver is possible via driver
parameters.
CANIO user parameter:
DRIVER_PARAMETER
Code
Content
DRIVER_PAR1
0 (default)
Access to diagnosis data deactivated
Process data (outputs) zeroed automatically
on PLC-STOP
DRIVER_PAR1
Bit 0 = 1
Activate access to diagnosis data
DRIVER_PAR1
Bit 1 = 1
Process data (outputs) not zeroed
automatically on PLC-STOP
DRIVER_PAR2
0 (default)
Process map update without use of
semaphores
Guarantees 32-bit data consistency, no
consistency over the complete map.
Fast with low overhead
Suitable for pure I/O accesses
DRIVER_PAR2
Bit 0 = 1
Process map update using semaphores
Data consistency over whole network
variable range
Slow and involving overhead, with waiting
time for enabling semaphores
Uses the timeout value from DRIVER_PAR3
e.g. for superimposed protocols
DRIVER_PAR2
Bit 1 = 1
Prevents task change during process data
update
DRIVER_PAR2
Bit 2 = 1
Double buffer mode, process map update
using semaphores
Data consistency over whole network
variable range
Fast but involving overhead, without waiting
time for enabling semaphores
e.g. for exchange of consistent data
structures
DRIVER_PAR3
Value
Timeout in µs (when semaphores are used)
default max. 500 µs
