Omron SYSMAC C1000H, Руководство по эксплуатации

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as LD, OUT, AND, and OR, nor can DM words be used with the SHIFT in-
struction.
The DM area retains status during power interruptions.
Normally, when the content of a data area word is specified for an instruction,
the instruction is performed directly on the content of that word. For example,
suppose CMP(20) (COMPARE), with IR 005 as the first operand and DM
0010 as the second operand, is used in the program. When this instruction is
executed, the content of IR 005 is compared with that of DM 0010.
It is also possible, however, to use indirect DM addresses as operands for
instructions. If
*
DM 0100 is specified as the data for a programming instruc-
tion, the asterisk in front of DM indicates that it is an indirect address that
specifies another DM word which contains the actual operand data. If, in this
case, the content of DM 0100 is 0324, then
*
DM 0100 indicates DM 0324 as
the word that contains the desired data, and the content of DM 0324 is used
as the operand in the instruction. The following example shows this type of
indirect addressing with the MOVE instruction (MOV(21)).
MOV(21)
*
DM 0100
LR 00
Word Content
DM 0099 4C59
DM 0100 0324
DM 0101 F35A
DM 0324 5555
DM 0325 2506
DM 0326 D541
5555 moved
to LR 00.
Indicates
DM 0324. Indirect
address
3-7 HR (Holding Relay) Area
The HR area is used to store/manipulate various kinds of data and can be
accessed either by word or by bit. Word addresses range from HR 00
through HR 99; bit addresses, from HR 0000 through HR 9915. HR bits can
be used in any order required and can be programmed as often as required.
The HR area retains status when the system operating mode is changed,
when power is interrupted, or when PC operation is stopped.
HR area bits and words can be used to to preserve data whenever PC op-
eration is stopped. HR bits also have various special applications, such as
creating latching relays with the KEEP instruction and forming self-holding
outputs. These are discussed in
Section 4 Writing and Inputting the Program
and Section 5 Instruction Set .
When a SYSMAC LINK System is used, a certain number of HR bits is re-
quired for a routing table and monitor timer. These bits are taken from be-
tween HR 00 to HR 42. Refer to the
SYSMAC LINK System Manual for de-
tails.
3-8 TC (Timer/Counter) Area
The TC area is used to create and program timers and counters and holds
the Completion flags, set values (SV), and present values (PV) for all timers
and counters. All of these are accessed through TC numbers ranging from
TC 000 through TC 511. Each TC number is defined as either a timer or
counter using one of the following instructions: TIM, TIMH, CNT, CNTR(12),
Indirect Addressing
TC Area
Section 3-8