Mitsubishi Electric QD62, Руководство пользователя

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MELSEC-Q
5 BASIC USAGE
5.2 Selecting the Counter Format
Select either linear counter or ring counter with the GX Developer intelligent function
module switch setting.
See Section 4.5 for details on the setting method.
5.2.1 Selecting the linear counter
(1) Linear counter operation
When the linear counter is selected, the count operation is performed between
–2147483648 (minimum value) and 2147483647 (maximum value).
The linear counter can be used in combination with the preset function and the
coincidence output function.
Overflow
Overflow
+ 2147483647
– 2147483648
Addition Subtraction
Counter present value
0
(2) Overflow error
(a) When the counter format is linear counter, an overflow error occurs if the
present counter value exceeds –2147483648 (minimum value) during
subtraction or exceeds 2147483647 (maximum value) during addition.
(b) When an overflow error occurs, 1 is stored in the buffer memory overflow
detection flag (addresses CH1: 8
H
, CH2: 28
H
) and the count stops. Even if a
pulse is input, the present value will not change from –2147483648 or
2147483647.
(c) Performing a preset will cancel the overflow error.
When a preset is performed, 0 is stored in the buffer memory overflow
detection flag and the count resumes.
(d) When an overflow error occurs, a generated module error can be viewed on
the system monitor by clicking "Diagnosis" - "System monitor" menu in the
GX Developer.