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8.1.2 Setting a counting method
Set a counting method by switch setting.
For details on the setting method, refer to the following.
• Switch Setting ( Page 54, Section 7.2)
8.1.3 Reading the present value
This section describes the details on the present value stored in the buffer memory and the count values selected from
the counter function selection, and their reading method.
(1) Storage location of the count value
The present value is always stored in CH Present value (Un\G2, Un\G3, Un\G34, Un\G35) regardless of the
counter function used.
When the latch counter, sampling counter, or periodic pulse counter function is performed, the count value is
stored in the corresponding buffer memory areas listed in the table below.
(2) Stored data
The present value and the counter function selection count values are stored in the buffer memory areas in 32-bit
signed binary.
The buffer memory data is automatically updated by counting operation. The latest count value can be read from
the buffer memory.
Read the present value and counter function selection count values by two words at a time.
If the values are read by one word at a time, the lower word data and the higher word data will be inconsistent when the
count value is updated during reading, and an incorrect count value may be read.
● Program example
● Inappropriate program example
The present value may change while CH1 Present value (L) (Un\G2) and CH1 Present value (H) (Un\G3) are read.
Description Present value
Counter function selection count value
Latch count
value
Sampling
count value
Periodic pulse
count
previous value
Periodic pulse
count current
value
Buffer memory address
CH1
Un\G2,
Un\G3
Un\G12,
Un\G13
Un\G14,
Un\G15
Un\G16,
Un\G17
Un\G18,
Un\G19
CH2
Un\G34,
Un\G35
Un\G44,
Un\G45
Un\G46,
Un\G47
Un\G48,
Un\G49
Un\G50,
Un\G51