User`s manual

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MELSEC-A
3 SPECIFICATION
3.6.2 A/D conversion enable/prohibit specification (Address RWwm)
(1) Set whether A/D conversion is enabled or disabled per channel.
(2) By setting the unused channels to conversion prohibit, the sampling cycle can be
shortened.
Example) The sampling cycle when only channels 1 and 3 are set to A/D
conversion enabled:
2 (Number of channels enabled) × 1ms (Conversion speed at one channel) = 2ms
(3) Operation is performed according to the setting made for the leading edges of
initial data setting request flag (RY(n+1)9).
(4) The default setting is A/D conversion disable for all channels.
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1
CH.2 CH.1
b0
Ignored
CH.3CH.4
1: Enable A/D conversion
0: Prohibit A/D conversion
CH.6 CH.5CH.7CH.8
(5) AJ65VBTCU-68ADV/ADI processing when conversion is
enabled/prohibited
(a) Average processing initialization
The data in the work area stored by the AJ65VBTCU-68ADV/ADI system to
perform the average processing is initialized.
For example, at a channel with the average processing specification at 50
times, if the conversion enable/prohibit is set after having completed
sampling for 30 times, the 30 sampling data is all cleared, and then the
average processing is performed from the initial state.
(b) A/D conversion completion flag processing
The A/D conversion completion flag processing is performed only once
when the A/D conversion enable/prohibit setting is changed.
• When changed the A/D conversion from prohibit to enabled:
When the average processing is specified, the flag turns on after
performing the average processing for the number of time or time and
storing the A/D conversion digital value in the remote register.
• When changed the A/D conversion from enabled to prohibited:
The A/D conversion completion flag for the corresponding channel is
turned off.