Rockwell Automation D64046.5.1 U MNL WIN DDMC - Manual (Page 51)

Configuring SDS Instructions
Chapter 4
4-15
The Ins Cmt (Instruction Comment) window on the I/O Definition screen
displays the instruction comment associated with the instruction in the ladder
program. The Adr Cmt (Address Comment) window displays the address
comment for the cursored address in the I/O Defines field.
The maximum number of possible inputs and outputs in the I/O Defines field
correlates with the number of I/O you entered in the Number of I/O field when
programming the SDS instruction.
Important: Consider carefully the order in which you assign I/O points in
the I/O Defines field. The order of I/O assignments can make a significant
difference in the performance of the DDMC32 system.
The order in which an SDS instruction checks I/O information is based on the
equations assigned in a given step (the “current” step). The order of evaluation
is as follows:
single bit transitions –– This includes all inputs that have an equation
assigned to them as ON–> OFF or OFF–> ON
combinatorial equations –– This includes any operations that contain
multiple inputs with either an AND or NOT operand
timers –– This includes any transitions that are generated by a timer (no
inputs are used for this transition)
You can perform the following tasks from the I/O Definition screen:
If you want to: Press this key:
Enter an operator interface station address. [F1] - Station Address
Enter a new timebase for the step timer. [F2] - Timebas
Enter the port number for the message. (PLC-5/250
only) [F3] - Port
Display the Documentation screen for the SDS
instruction. [F5] - Documnt
Modify an I/O address at the cursored location. [F7] - Modify IO Addr
Insert an I/O address at the cursored location. 1 [F8] – Insert IO Addr
Delete an I/O address at the cursored location. 1 [F9] – Delete IO Addr
Remove an I/O address at the cursored location. 1 [F10] – Remove IO Addr
1 These function keys do not appear on the screen if you have accepted edits once (for example, if you are
modifying the instruction).