Sr (Special Relay) Area - Omron C200H Operation Manual

SR Area
Allocation for Optical I/O
Units
Allocation for Remote I/O
Master and Link Units
Bit Allocation for I/O Units
3-4

SR (Special Relay) Area

20
two Masters are used. IR area words are allocated to Special I/O Units and
Slave Racks by the unit number on the unit, as shown in the following tables.
Special I/O Units
Unit number IR address
0 100 to 109
1 110 to 119
2 120 to 129
3 130 to 139
4 140 to 149
5 150 to 159
6 160 to 169
7 170 to 179
8 180 to 189
9 190 to 199
The C500-RT 001/002-(P)V1 Remote I/O Slave Rack may be used, but it
requires 20 I/O words, not 10, and therefore occupies the I/O words allocated
to 2 C200H Slave Racks, both the words allocated to the unit number set on
the rack and the words allocated to the following unit number. When using a
C200H CPU Unit, do not set the unit number on a C500 Slave Rack to 4, be-
cause there is no unit number 5. I/O words are allocated only to installed
units, from left to right, and not to slots as in the C200H system.
I/O words between IR 200 and IR 231 are allocated to Optical I/O Units by
unit number. The I/O word allocated to each unit is IR 200+n, where n is the
unit number set on the unit.
Remote Master I/O Units, SYSMAC LINK Units, SYSMAC NET Link Units,
and Host Link Units do not use I/O words, and the PC Link Units use the LR
area, so words allocated to the slots in which these units are mounted are
available as work words.
An I/O Unit may require anywhere from 8 to 16 bits, depending on the model.
With most I/O Units, any bits not used for input or output are available as
work bits. Transistor Output Units C200H-OD213 and C200H-OD411, as well
as Triac Output Unit C200H-OA221, however, uses bit 08 for the Blown Fuse
Flag. Transistor Output Unit C200H-OD214 uses bits 08 to 11 for the Alarm
Flag. Bits 08 to 15 of any word allocated to these units, therefore, cannot be
used as work bits.
The SR area contains flags and control bits used for monitoring PC opera-
tion, accessing clock pulses, and signalling errors. SR area word addresses
range from 236 through 255; bit addresses, from 23600 through 25507.
The following table lists the functions of SR area flags and control bits. Most
of these bits are described in more detail following the table. Descriptions are
in order by bit number except that Link System bits are grouped together.
Unless otherwise stated, flags are OFF until the specified condition arises,
when they are turned ON. Restart bits are usually OFF, but when the user
Slave Racks
Unit number IR address
0 050 to 059
1 060 to 069
2 070 to 079
3 080 to 089
4 090 to 099
Section 3-4