Omron GRT1-CRT - 05-2008, Operation Manual

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I/O Allocations to CompoNet Master Unit Section 5-3
Bits That Are Not
Used
The figure below shows a 4-bit Unit (Unit 5) that gets two bits in one word and
two bits in the subsequent word. The subsequent Unit (Unit 6) is a Word Unit
that gets two words. The system allocates the subsequent two full words to
this Unit and does not allocate the other bits in the +1 word.
Unit 8 in the figure is an 8-bit Unit. The system allocates only full words to 8-
bit Units. In this example, the system allocates the subsequent full word (the
+5 word) and does not allocate the other bits in the +4 word. (The first four bits
in the +4 word are for Unit 7.)
5-3-2 Restrictions for Data Sizes and Number of Units
There are restrictions on the SmartSlice I/O Units that you can connect to one
CompoNet Communications Unit. The restrictions are for the number and
models of SmartSlice I/O Units that you connect.
• You can connect a maximum of 64 SmartSlice I/O Units. (This does not
include the End Unit.)
• The Input Area must be no larger than 32 bytes. This includes bits for
Word Units, bits for Bit Units, status words, and bits that are not used.
• The Output Area must be no larger than 32 bytes. This includes bits for
Word Units, bits for Bit Units, and bits that are not used.
These are examples of the restrictions.
Permitted Configurations • Bit Input Units Only
8
+1
+0 #5 #4 #3 #2 #1
#5
#6
+2
+3
#1
OD4
#2
OD4
#3
OD4 #4
ROS2
#5
OD4
#6
DA2
#7
OD4 #8
OD8
+4 #7
+5 #8
Configuration Example for Slice I/O Terminal
CompoNet
Communi-
cations
Unit
The system allocates four bits to a 4-bit
Unit two bits at a time. It allocates the bits
in sequence in the same word or in
different words.
Word
Bit 15
Bit 0
Not used.
Not used.
Not used.
The system allocates a
full word to a 8-bit Unit.
This makes bits that are
not used.
The system will not output data that you write
to these bits.
CompoNet
Communications
Unit
4-point
DC Input
Unit
4-point
DC Input
Unit
4-point
DC Input
Unit
4-point
DC Input
Unit
End Unit
60 Units
Four-point DC Input Unit (GRT1-ID4): 4 bits
×
60 = 30 bytes in Input Area
Two bytes are used for CompoNet Communications Unit status. The total is 32 bytes.