19
Expansion I/O Racks An Expansion I/O Rack can be thought of as an extension of the PC because it
provides additional slots to which other Units can be mounted. It is built onto an
Expansion I/O Backplane to which a Power Supply and up to ten other Units are
mounted.
An Expansion I/O Rack is always connected to the CPU via the connectors on
the Backplanes, allowing communication between the two Racks. Up to two Ex-
pansion I/O Racks can be connected in series to the CPU Rack.
Unit Mounting Position Only I/O Units and Special I/O Units can be mounted to Slave Racks. All I/O
Units, Special I/O Units, Group-2 High-density I/O Units, Remote I/O Master
Units, PC and Host Link Units, can be mounted to any slot on all other Racks.
Interrupt Input Units must be mounted to C200H-BCjj1-V2 Backplanes.
Refer to the
C200HS Installation Guide
for details about which slots can be used
for which Units and other details about PC configuration. The way in which I/O
points on Units are allocated in memory is described in
3-3 IR Area
.
2-3 CPU Capabilities
The following tables compare the capabilities of C200H and C200HS CPUs.
C200H
Function C200H
CPU21-E CPU23-E CPU31-E
Built-in clock/calendar No (see note) No (see note) Yes
Error log No No Yes
Data Trace No No No
Differential Monitor No No No
Expansion DM No No No
General-use DM 1000 words 970 words
Ladder Program capacity 6974 words (in Memory Unit)
SR Area SR 236 to SR 255
New instructions:
(See
1-8-3 Larger Instruction Set
for a list of the
36 new instructions.)
No No No
Network Instructions:
NETWORK SEND - SEND(90)
NETWORK RECEIVE - RECV(98)
No No Yes
Power Supply AC DC AC
Note The C200H-CPU21-E/CPU23-E can use the C200H-MR433/MR833/
ME432/ME832 Memory Units’ clock.
CPU Capabilities Section 2-3
