Functions; I/O Unit Interface Specifications - Omron PRT1-COM Operation Manual

Functions

3-2

Functions

3-2-1 I/O Unit Interface Specifications

Item
Communications method
Number of I/O Units
Maximum number of data bytes Input data: 128 bytes
Communica- Total length
tions distance i di
Between
Units
Communications power supply
Relationship to PROFIBUS-DP After the I/O Unit interface is established, PROFI-
Addresses
I/O configuration
Self-diagnostic Configuration
functions
errors
Special I/O
Unit errors
I/O Unit inter-
face errors
Power supply
overload to
I/O Units
Error detection
Specification
Special protocol
8 Units max.
Output data:128 bytes
3 m max.
1 m max. (Cable included with Unit is 40 mm.)
Supplied from the Communication Unit to the I/O
Unit (0.3 A max.)
BUS-DP communications continue normally, even
if an error occurs on the I/O Unit interface.
Automatically recognised when the power to the
Communication Unit is turned ON.
Automatically recognised when the power to the
Communication Unit is turned ON. If the configu-
ration is changed while the power supply is ON, a
configuration error will occur.
The I/O Unit configuration is constantly checked
while power is supplied. If a mismatch occurs
while the power is turned ON, I/O refreshing for all
I/O Units is stopped.
Errors are detected in the Special I/O Units (Ana-
log Input, Analog Output Units, and Counter Units)
on the I/O Unit interface.
Communications stop when there is no commu-
nications response from an I/O Unit.
Communications stop when there is no specific
response from the last I/O Unit (terminator).
Communications stop when nine or more I/O
Units are connected.
The power supply to the I/O Units and I/O refresh-
ing for all I/O Units are stopped when the power
supply to the I/O Units through the Communica-
tion Unit exceeds 0.3 A.
Frame error check; CRC-CCITT check
Section 3-2
29