Omron SYSMAC C1000H, Руководство по эксплуатации

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the program execution moves to the next instruction. When memory is
cleared prior to programming, NOP(00) is written at all addresses. NOP(00)
can be input through the 00 function code.
There are no flags affected by NOP(00).
5-12 Timer and Counter Instructions
TIM and TIMH are decrementing ON-delay timer instructions which require a
TC number and a set value (SV).
CNT is a decrementing counter instruction and CNTR is a reversible counter
instruction. Both require a TC number and a SV. Both are also connected to
multiple instruction lines which serve as an input signal(s) and a reset.
Any one TC number cannot be defined twice, i.e., once it has been used as
the definer in any of the timer or counter instructions (including timer and
counter block instructions discussed in
5-20 Block Instructions ), it cannot be
used again. Once defined, TC numbers can be used as many times as re-
quired as operands in instructions other than timer and counter instructions.
TC numbers run from 000 through 511. No prefix is required when using a
TC number as a definer in a timer or counter instruction. Once defined as a
timer, a TC number can be prefixed with TIM for use as an operand in certain
instructions. The TIM prefix is used regardless of the timer instruction that
was used to define the timer. Once defined as a counter, a TC number can
be prefixed with CNT for use as an operand in certain instructions. The CNT
is also used regardless of the counter instruction that was used to define the
counter.
TC numbers can be designated as operands that require either bit or word
data. When designated as an operand that requires bit data, the TC number
accesses a bit that functions as a ‘Completion Flag’ that indicates when the
time/count has expired, i.e., the bit, which is normally OFF, will turn ON when
the designated SV has expired. When designated as an operand that re-
quires word data, the TC number accesses a memory location that holds the
present value (PV) of the timer or counter. The PV of a timer or counter can
thus be used as an operand in CMP(20), or any other instruction for which
the TC area is allowed. This is done by designating the TC number used to
define that timer or counter to access the memory location that holds the PV.
Note that “TIM 000” is used to designate the Timer instruction defined with
TC number 000, to designate the Completion Flag for this timer, and to des-
ignate the PV of this timer. The meaning of the term in context should be
clear, i.e., the first is always an instruction, the second is always a bit oper-
and, and the third is always a word operand. The same is true of all other TC
numbers prefixed with TIM or CNT.
An SV can be input as a constant or as a word address in a data area. If an
IR area word assigned to an Input Unit is designated as the word address,
the Input Unit can be wired so that the SV can be set externally through
thumbwheel switches or similar devices. Timers and counter wired in this
way can only be set externally during RUN or MONITOR mode. All SVs, in-
cluding those set externally, must be in BCD.
Flags
Timer and Counter Instructions
Section 5-12