5-1
Section
Memory Area Functions
312
program branches. They are used only for mnemonic code. When programming
directly with ladder diagrams using the SYSMAC Support Software (SSS) or the
SYSMAC-CPT Support Software, TR bits are automatically processed for you.
The same TR bits cannot be used more than once within the same instruction
block, but can be used again in different instruction blocks. The ON/OFF status
of TR bits cannot be monitored from a Programming Device.
Examples showing the use of TR bits in programming are provided on page 350.
HR Area
These bits retain their ON/OFF status even after the PC power supply has been
turned off or when operation begins or stops. They are used in the same way as
work bits.
AR Area
These bits mainly serve as flags related to PC operation. These bits retain their
status even after the PC power supply has been turned off or when operation
begins or stops. For details on the various bit functions, refer to relevant sections
in this manual or to
Appendix C Memory Areas
.
LR Area
When the CPM1/CPM1A/CPM2A/CPM2C/SRM1(-V2) is linked 1:1 with anoth-
er CPM1/CPM1A/CPM2A/CPM2C/SRM1(-V2), a CQM1, an C200HS or
C200HX/HG/HE PC, these bits are used to share data. For details, refer to page
229.
LR bits can be used as work bits when not used for 1:1 PC Links.
Timer/Counter Area
This area is used to manage timers and counters created with TIM, TIMH(15),
TMHH(––)*, TIML(––)*, CNT, and CNTR(12). The same numbers are used for
both timers and counters and each number can be used only once in the user
program. Do not use the same TC number twice even for different instructions.
Use TC numbers 000 through 003 for TIMH(15) and TC numbers 004 to 007 for
TMHH(––)*. When these timer numbers are used, timing is performed as an in-
terrupt process and the cycle timer does not affect timer operation.
TC numbers are used to create timers and counters, as well as to access
Completion Flags and present values (PVs). If a TC number is designated for
word data, it will access the present value (PV); if it is used for bit data, it will ac-
cess the Completion Flag for the timer/counter.
Refer to instructions beginning on page 388 for details on timers and counters.
DM Area
DM area data is accessed in word units only. The contents of the DM area are
retained even after the PC power supply has been turned off or when operation
begins or stops.
CPM1/CPM1A
DM words DM 0000 through DM 0999, DM 1022, and DM 1023 can be used
freely in the program; other DM words are allocated specific functions, de-
scribed below.
DM 1000 through DM 1021 contain the error log information. Refer to
Section 9
Troubleshooting
for details on the error log.
CPM2A/CPM2C
DM words DM 0000 through DM 1999 and DM 2022 through DM 2047 can be
used freely in the program; other DM words are allocated specific functions, de-
scribed below.
DM 2000 through DM 2021 contain the error log information. Refer to
Section 9
Troubleshooting
for details on the error log.
SRM1(-V2)
DM words DM 0000 through DM 1999 can be used freely in the program; other
DM words are allocated specific functions, described below.
DM 2000 through DM 2021 contain the error log information. Refer to
Section 9
Troubleshooting
for details on the error log.
Note
DM 6600 through DM 6655 contain the PC Setup. Refer to
1-1 PC Setup
for de-
tails.
