Scanner Configuration; Example Program - Allen-Bradley 1747-SN User Manual

Scanner Configuration

The baud rate is 115.2K. DIP switch 1 should be in the ON position;
DIP switch 2 should be OFF.
The G file size is set to 3 using the Specialty I/O Configuration
function. The M0 and M1 file sizes are set to 32 in the Advanced Set
Up function.
Since only the first 4 words of the input and output files contain
valid information, the scanned input and output words can be set to
4. Reducing the number of scanned input and output words
decreases your SLC scan time.
Configuration information is entered in the Modify G File function.
Word 0 is reserved, and therefore, cannot be modified. Word 1
indicates the starting address of the device; word 2 indicates its size.

Example Program

The example program is shown below. Each time a function key is
pressed on the RediPANEL, its associated message is displayed.
This program also monitors the scanner's Enabled Device Fault bit
(M1:1.0/0). If communications is lost, an alarm is activated.
If the Communications attempted and
Enabled Device Fault bits are set to 1,
activate the alarm.
If function key 1 is pressed (bit 8 of
input word 0), T4:0 Preset is moved
to the display.
When a new number is entered
onto the RediPANEL, it is moved to
preset T4:0.
If function key 2 is pressed (bit 9 of
input word 0), RediPANEL message
#2 is triggered and displayed.
Application Examples
MEQ
MASKED EQUAL
Source M1:1.0
Mask 0003
Compare 3
I:1.0
] [
8
I:1.0
] [
14
I:1.0
] [
9
O:2
( )
MOV
MOVE
Source T4:0.PRE
Dest O:1.1
MOV
MOVE
Source I:1.1
Dest T4:0.PRE
MOV
MOVE
Source
Dest O:1.2
END
Publication 1747 6.6 - July 1996
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