
8.CONNECTION TO FANUC I/O Link B-63943EN/02
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8.4.14 Analog Input Specifications
(Digital output)
This digital input module has four input channels. The digital output
section consists of a group of 12 bits within the three-byte occupied
input points. The output format is indicated below.
Address in the module 7 6 5 4 3 2 1 0
Xm (even-numbered address) D07 D06 D05 D04 D03 D02 D01 D00
Xm+1 (odd-numbered address) 0 0 CHB CHA D11 D10 D09 D08
D00 to D11 represent 12-bit digital output data. D00 and D11
correspond to weightings of 2
0
and 2
11
, respectively.
D11 is a sign bit expressed as a two's complement. CHA and CHB
represent analog input channels. This means that when the two bytes
above are read with a PMC program, the A-D converted data of the
CHA and CHB input channels can be read from D11 to D00. For
CHA and CHB, see the description of channel selection, below.
Section 6.3 provides notes on reading data with a PMC program.
(Channel selection)
With this analog input module, which of the four channels is to be
output to the digital output section must be determined with a PMC
program. The DO points used for this selection are CHA and CHB
(two-byte occupied output points). These are mapped as indicated
below.
Address in the module 7 6 5 4 3 2 1 0
Yn X X X X X X X X
Yn+1 X X X X X X CHB CHA
By writing the values indicated below to CHA and CHB, the
corresponding channel is selected, and the A-D converted data of the
channel and the data of the selected channel can be read as DI data.
The character X indicated above represents an unused bit, so that
either 1 or 0 may be written in place of X.
CHB CHA Channel selected
0 0 Channel 1
0 1 Channel 2
1 0 Channel 3
1 1 Channel 4