User Manual Owner manual

Chapter 2
Planning to Use Your ControlNet
PLC5 Processor
2-2
A similar method is used for all scheduled data-transfer operations.
Housekeeping
Program Scan
Data
Table
Files
Scheduled Data Transfer
Private
Memory
Buffers
Scheduled Data Transfers
Data Update
Logic Scan
The following scheduled data-transfer operations are supported by the
PLC-5/20C and -5/40C processors on a ControlNet network:
Table 2.A
ControlNet
Scheduled DataT ransfer Operations
Operation Description
Discrete I/O Data Transfer
Performed in a deterministic and repeatable manner
asynchronous to and independent of the ladderlogic
program scan. You configure all ControlNet discrete I/O
data transfers on a pernode basis in the I/O map table.
①
Nondiscrete I/O Data Transfer
Handled with the same priority as discrete I/O data transfer.
You can update analog data without using blocktransfer
instructions in ladder programs. You do this by including
nondiscrete I/O datatransfer configurations in the I/O map
table. This data is updated in the buffers and datatable
files between logic scans in the same manner as that used
in discrete I/O data transfer.
①
Peertopeer Communication
Allows the controlling" processor at network address 01
to communicate with other ControlNet processors on the
ControlNet network with the same priority as that of the
discrete and nondiscrete I/O data transfers discussed
above.
①
①
While scheduled data transfer is asynchronous to program scanning, all data is presented
synchronously to the processor and output buffers during housekeeping.