Mitsubishi QD60P8-G, User Manual

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MELSEC-Q
5 DETAILS AND SETTING OF FUNCTIONS
5.3 Input Pulse Value
The pulse number entered into the QD60P8-G is stored into the "input pulse
value" of the buffer memory. This value is counted when the count enable (Y18
to Y1F) is ON.
The input pulse value is not converted into the unit pulse number by the pre-scale
function (refer to Section 5.6), unlike the "sampling pulse number" and
"accumulating count value" of the buffer memory. If an overflow error occurs, the
value is counted when the count enable (Y18 to Y1F) is ON.
The count type of the input pulse value is a ring counter of 0 to 2147483647.
Input pulse
value 2147483647 0 1 2 3 2147483646 2147483600
Input pulse count value of 2147483647
incremented by 1 turns to 0.
to
Buffer memory address
Item Read value
CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH8
Input pulse value 0 to 2147483647
10
11 42
43 74
75 106
107 138
139 170
171 202
203 234
235
The buffer memory addresses for resetting the input pulse values are as follows.
Buffer memory address
Item
CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH8
Counter reset request 13 45 77 109 141 173 205 237
POINT
• The update timing of the input pulse value is fixed at 10ms. Therefore, take care
when using the module as a counter. (Refer to Section 5.9)
• When reading the input pulse value, always read two words together.
If it is read in single word unit, a wrong count value may be read due to a data
mismatch between the lower word and upper word when the count value is
updated halfway during read.