Omron SYSMAC C1000H, Руководство по эксплуатации

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An actual data location within any data area but the TC area is designated by
its address. The address designates the bit or word within the area where the
desired data is located.
The TC area consists of TC numbers, each of which
is used for a specific timer or counter defined in the program. Refer to 3-7 TC
Area for more details on TC numbers and to 5-11 Timer and Counter Instruc-
tions for information on their application.
The rest of the data areas (i.e., the IR, SR, HR, DM, AR, and LR areas) con-
sist of words, each of which consists of 16 bits numbered 00 through 15 from
right to left. IR words 000 and 001 are shown below with bit numbers. Here,
the content of each word is shown as all zeros. Bit 00 is called the rightmost
bit; bit 15, the leftmost bit.
The term least significant bit is often used for rightmost bit; the term most
significant bit, for leftmost bit. These terms are not used in this manual be-
cause a single data word is often split into two or more parts, with each part
used for different parameters or operands. When this is done, the rightmost
bits of a word may actually become the most significant bits, i.e., the leftmost
bits in another word,when combined with other bits to form a new word.
Bit number
IR word 000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
IR word 001 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
The DM area is accessible by word only; you cannot designate an individual
bit within a DM word. Data in the IR, SR, HR, AR, and LR areas is accessible
either by word or by bit, depending on the instruction in which the data is be-
ing used.
To designate one of these areas by word, all that is necessary is the acronym
(if required) and the two-, three-, or four-digit word address. To designate an
area by bit, the word address is combined with the bit number as a single
four- or five-digit address. The following table show examples of this. The two
rightmost digits of a bit designation must indicate a bit between 00 and 15,
i.e., the rightmost digit must be 5 or less the next digit to the left, either 0 or 1.
The same TC number can be used to designate either the present value (PV)
of the timer or counter, or a bit that functions as the Completion flag for the
timer or counter. This is explained in more detail in
3-7 TC Area .
Area Word designation Bit designation
IR 000 00015 (leftmost bit in word 000)
SR 252 25200 (rightmost bit in word 252)
DM DM 1250 Not possible
TC TC 215 (designates PV) TC 215 (designates Completion Flag)
LR LR 12 LR 1200
Word data input as decimal values is stored in binary-coded decimal (BCD);
word data entered as hexadecimal is stored in binary form. Each four bits of
a word represents one digit, either a hexadecimal or decimal digit, numeri-
cally equivalent to the value of the binary bits. One word of data thus con- Data Structure
Data Area Structure
Section 3-2