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C200HW-SRM21-V1 Master Unit for CS-series, C200HX/C200HG/C200HE-(Z)E, and C200HS PLCs
Section 4-1
• The Master Unit is factory-set to OFF (for IN0 to IN7 and OUT0 to OUT7).
• The maximum number of Slaves setting affects both the total number of
words allocated and the Slaves’ communication cycle. Refer to
Allocations in CS-series, C200HX/C200HG/C200HE-(Z)E, and C200HS
PLCs
for details.
• The Master Unit is allocated twice as many words in the PLC’s Special I/O
Unit Area (the words for unit number set on the Master and the next unit
number) when the usable node number setting is set to IN0 to IN15 and
OUT0 to OUT15. In this case, neither the Master’s unit number nor the
next unit number can be used on another Special I/O Unit mounted in the
PLC.
• Pin 2 is factory-set to OFF (High-speed Communications Mode).
• The setting of pin 2 determines the communications distance, baud rate,
and cycle time as shown in the above table.
4-1-3
I/O Allocations in CS-series, C200HX/C200HG/C200HE-(Z)E, and
C200HS PLCs
In CS-series, C200HX/C200HG/C200HE-(Z)E, and C200HS PLCs, the Mas-
ter Unit is treated as a Special I/O Unit, so the Slave’s I/O data and status
information are stored in the sections of the PLC’s data areas which are allo-
cated to Special I/O Units.
Allocations and Master
Unit Settings
The following settings affect I/O allocations to Slaves in the Master Units used
with CS-series, C200HX/C200HG/C200HE-(Z)E, and C200HS PLCs.
Slave Allocations
Slaves are allocated words in the Special I/O Unit Area as described next. In
CompoBus/S Systems, node numbers of Input Slaves and Output Slaves are
treated separately so the same node number can be allocated.
I/O Allocations when Pin 1 Is OFF
When pin 1 is OFF and node addresses IN0 to IN7 and OUT0 to OUT7 (up to
64 inputs/64 outputs) are used, words are allocated to the Slaves for each
node number as shown in the following diagrams.
Setting at Master
Unit
Status
Affect on allocation
Usable node num-
ber settings (DIP
switch pin 1)
OFF
Uses 10 words (for one unit number) from the Special
I/O Unit Area as follows:
Output: 4 words, input: 4 words, status: 2 words.
ON
Uses 20 words (for two unit numbers) from the Special
I/O Unit Area as follows:
Output: 8 words, input: 8 words, status: 4 words.
Unit number set-
ting (rotary switch)
n
First word of the area used in the Special I/O Unit Area
CS Series
2000 + n
×
10
C200HX/HG/HE/HS
For 0
≤
n
≤
9: 100 + n
×
10
For 10
≤
n
≤
15 (A to F): 400 + (n
−
10)
×
10