Chapter 4 – Rockwell Automation 1785-L20C_L40C, D17856.5.14 ControlNet PLC-5 Programmable Controllers User Manual User Manual

Page 61

Chapter 4

Programming Your ControlNet System

4-6

You can use two instructions for immediate data input and output
on a ControlNet network—Immediate Data Input (IDI) and Immediate
Data Output (IDO).

Follow the steps on the left to add IDI and IDO instructions to your
program.

IDI

IMMEDIATE DATA INPUT

Data file offset 232

Length 10

Destination N11:232

IDO

IMMEDIATE DATA OUTPUT

Data file offset 175

Length 24

Source N12:175

[END OF FILE]

Press a function key.

(File 2: Rung 0)

Rem Prog Forces:None Edits:None 5/40C File CN

Change Config Return Program Documnt Search General Data Force Edit

Mode Display to Menu Dirctry Utility Monitor

F1 F2 F3 F4 F5 F6 F7 F8 F9 F10

In the example above, an IDI is initiated that updates the destination file
from the private buffer before the next normal input-image update. The
Data File Offset (232) is the offset into the buffer where the data is stored.
The Length (10) identifies the number of words in the transfer—it can be
an immediate value ranging from 1 to 64 or a logical address that specifies
the number of words to be transferred. The Destination (N11:232) is the
destination of the words to be transferred. The Destination should be the
matching data-table address in the DIF except when you use the instruction
to ensure data-block integrity in the case of Selectable Timed Interrupts
(STIs). See page 4-7.

An IDO is initiated that updates the private memory output buffer from the
source file before the next normal output- image update. The Data File
Offset (175) is the offset into the buffer where the data is stored. The
Length (24) identifies the number of words in the transfer or a logical
address that specifies the number of words to be transferred. The Source
(N12:175) is the source of the words to be transferred. The Source should
be the matching data-table address in the DOF except when you use the
instruction to ensure data-block integrity in the case of Selectable Timed
Interrupts (STIs). See page 4-7.

Using ControlNet Immediate

Data Input and Output

Instructions

Monitor

File

6200

Main Menu

Cursor to file;

Online

Program

Offline

Program

F10

Insert

Rung

Edit

Others

F10

Insert

Instruction

IDI

or enter file number or name

I/O

Message

or IDO