Omron CVM1D, Operation Manual

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and its set value (SV) are defined using counter instructions. No prefix is re-
quired when using a counter number to create a counter in a counter instruction.
The same counter number can be defined using more than one of these instruc-
tions as long as the instructions are not executed in the same cycle. If the same
counter number is defined in more than one of these instructions or in the same
instruction twice, an error will be generated during the program check, but as
long as the instructions are not executed in the same cycle, they will operate cor-
rectly. There are no restrictions on the order in which counter numbers can be
used.
Once defined, a counter number can be designated as an operand in one or
more of certain instructions other than those listed above. Counter numbers can
be designated for operands that require bit data or for operands that require
word data. When designated as an operand that requires bit data, the counter
number accesses the completion flag of the counter. When designated as an
operand that requires word data, the counter number accesses a memory loca-
tion that holds the PV of the counter.
Counter PVs are reset when the CNR(236) instruction is executed, but unlike
timers, counters maintain their status when PC operation is begun, and when in
interlocked program sections when the execution condition for IL(002) is OFF.
Counter Completion Flags are allocated to internal I/O memory addresses (bit
addresses) F800 through F8FF, corresponding to counter numbers C0000
through C1023. Counter PVs are allocated to internal I/O memory addresses
(word addresses) 1800 through 1BFF, corresponding to counter numbers
C0000 through C1023. Completion Flags and PVs can be accessed directly with
their internal I/O memory addresses, but they are normally accessed by using
the counter numbers in the program.
3-9 DM and EM Areas
The DM (Data Memory) Area is used for internal data storage and manipulation
and is accessible only by word. Addresses range from D00000 through D24575.
The EM (Extended Data Memory) Area is contained in the CV1000-DM
jj
1
EM Unit, a card which must be purchased separately and installed into a slot on
the CPU Unit in order for the EM Area to be used. There are three models of
Memory Units available, with 64K words (E00000 to E32765
×
2 banks), 128K
words (E00000 to E32765
×
4 banks), and 256K words (E00000 to E32765
×
8
banks).
When the PC is turned on, the EM bank number is automatically set to 0, but can
be changed with the EMBC(171) instruction.
When using the SYSMAC NET Link or SYSMAC LINK systems, D00000
through D00127 are automatically allocated as part of the Data Link Table un-
less data link are set manually from the SSS. The 1,600 words from D02000 to
D03599 are allocated for CPU Bus Units, 100 words for each Unit. The particular
function depends on the type of CPU Bus Unit being used. Refer to the CPU Bus
Unit’s Operation Manual for details.
Note D02000 to D03599 are not used by SYSMAC BUS/2 Remote I/O Master Units.
Although composed of 16 bits just like any other word in memory, DM and EM
words cannot be specified by bit for use in instructions with bit-size operands,
such as LD, OUT, AND, and OR, nor can DM words be used with the SHIFT
instruction.
The DM and EM Areas retain 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, sup-
pose CMP(020) (COMPARE) is used in the program with CIO 0005 as the first Indirect Addressing
DM and EM Areas
Section 3-9