Mitsubishi Electric MELSEC FX3U Programming Manual page 775

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
Cautions
1. LOGR instruction
LOGR instruction executes logging in each operation in the continuous operation type.
When logging should be executed only once by one input, use the pulse operation type.
2. Caution on using a memory cassette
Flash memory is adopted in a memory cassette. Make sure to initialize the data storage area in units of
sector before starting logging.
If LOGR instruction is executed without initializing the data storage area, an operation error (error code:
K6770) may be caused.
Logging data storage area initialization
command input
*1 Specify the same device as
*2 Specify the same number as (n) in LOGR instruction.
3. Allowable number of writes to the memory
Note the following cautions on access to extension file registers.
• Data can be written to the memory cassette (flash memory) up to 10,000 times.
Every time the INITR (FNC292), RWER (FNC294) or INITER (FNC295) instruction is executed, it is
counted as a write to the memory. Make sure not to exceed the allowable number of writes.
When a continuous operation type instruction is used, data is written to the memory in every operation
cycle of the PLC. For preventing this, make sure to use a pulse operation type instruction.
• Execution of the LOADR (FNC290), SAVER (FNC291) or LOGR (FNC293) instruction is not counted as a
write to the memory. However, it is necessary to initialize the writing target sector before executing the
SAVER (FNC291) or LOGR (FNC293) instruction.
Every time the INITR (FNC292)or INITER (FNC295) instruction is executed, it is counted as a write to the
memory. Make sure not to exceed the allowable number of writes.
33 Extension File Register Control – FNC290 to FNC299
*1
FNC292
D
1
INITR
D
1 in LOGR instruction.
33.4 FNC293 – LOGR / Logging R and ER
*2
n
31
32
33
34
35
36
37
38
A
B
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