Rockwell Automation 2705 REDIPANEL KEYPAD MODULE USER MANUAL - Manual (Page 51)

Chapter 7
Programming
7–13
be reflected in this file. Therefore, all your input or output addresses for
these remote devices will be elements of this file.
•
LENGTH is the number of words the sub I/O scanner is transferring. The
number entered will be equal to 8 words (reserved for sub I/O scanner
utility functions) plus 2 words for each 1/4 rack of I/O the sub I/O scanner
will be communicating with. For example: If you are connecting 4
RediPANELs configured for 1/4 rack, plus 1 RediPANEL configured for
1/2 rack to the sub I/O scanner, the number you would enter here would
be 20.
8 words (for sub I/O scanner utility functions)
+8 words (2 words for each 1/4 rack RediPANEL)
+4 words (for the one, 1/2 rack RediPANEL)
=20 words
•
CONTINUOUS determines the mode of instruction execution. Enter N,
for no.
It is important to note, that all block transfer read and write instructions
should be programmed in the first rungs of the program. Each instruction
may transfer a maximum of 64 words at a time between the processor and the
sub I/O scanner. (8 words for the sub I/O scanner utility functions and 8
words for each of the 7 logical racks of RediPANELs the sub I/O scanner is
capable of communicating to.)
Programming Example
In this programming example, we are using block transfer read and write
instructions to communicate between a PLC–5/15 and sub I/O scanner. The
sub I/O scanner is located in slot 1, module group 7 of the local I/O rack.
The sub I/O scanner has a keypad module, configured for 1/2 rack, connected
to it.