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Analog I/O Modules (AD268 / DA264 / TC218)
5. I/O Allocation and Programming
PART 3 TC218
5.3 Programming
To read the A/D conversion data, there is no need to use special instruction. The A/D
conversion data are automatically stored in the assigned input registers (XW registers).
For example, when the TC218 is allocated to XW000 to XW007, the A/D conversion data of
each channel is stored as follows.
XW000 :
Channel 1 A/D conversion data
XW001 :
Channel 2 A/D conversion data
XW002 :
Channel 3 A/D conversion data
XW003 :
Channel 4 A/D conversion data
XW004 :
Channel 5 A/D conversion data
XW005 :
Channel 6 A/D conversion data
XW006 :
Channel 7 A/D conversion data
XW007 :
Channel 8 A/D conversion data
Therefore, in the user program, you can use these XW registers directly for the analog data
processing.
The program shown below is an example of simple comparison with the channel 2 input data.
(Thermocouple type K setting)
By the above program, the ON/OFF status of the internal relays R0200 to R0203 are changed
as follows.
Status of the internal relays
Temperature
XW001 data
R0200
R0201
R0202
R0203
More than 550
°
C
11000
<
XW001
ON
ON
OFF
OFF
510 to 550
°
C
10200
<
XW001
≤
11000
OFF
ON
OFF
OFF
490 to 510
°
C
9800
≤
XW001
≤
10200
OFF
OFF
OFF
OFF
450 to 490
°
C
9000
≤
XW001
<
9800
OFF
OFF
ON
OFF
Less than 450
°
C
XW001
<
9000
OFF
OFF
ON
ON
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