User`s manual

DeviceNet (Master) Function
8-34
8
8-5 Communication timing
This chapter describes DeviceNet section the communication between the JW-32CUM1 (control section),
the JW-32CUM1 (DeviceNet section: master), and the slave stations when using the JW-32CUM1 as the
master mode.
To exchange data between the DeviceNet section and the control section, the control section executes as
optional process.
Data exchange using
data exchange memory
I/O message
communication
Data exchange memory Optional processing
(Control section processing)
Input/output processing
User program
processing
(DeviceNet section:
Process of master station)
Hardware check
The DeviceNet section receives responses from all slave stations. If not, after a communication time out,
it will complete one I/O message communication cycle, and exchange data with the control section.
- The time-out time is the normal time required after the DeviceNet section completes sending commands
to all of the slave stations, until it receives responses from all of the slave stations. The actual
communication time-out period is determined by the setting of Switch SW8 (selection of communication
monitor time) on the JW-32CUM1 and the number of slave stations connected. - See page 8-11.
The division of the communication timing between the I/O message communication time and the
operation time of the JW-32CUM1 (control section) is as follows.
[1] When the I/O message communication time is shorter than the JW-32CUM1
(control section) cycle operation time
Communication cycle: Asynchronous/synchronous
Operation of the
control section
Operation of the
DeviceNet section
I/O message communication
Optional processing Optional processing Optional processing
Slave stations (maximum 63 nodes)
Command
Command
Response
Response
User program/Input and output processing User program/Input and output processing
Waiting time Waiting time
12 63
Slave stations (maximum 63 nodes)
12 63
JW-32CUM1