User`s manual

Chapter 4 Features and Functions

Digital I/O Operation

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Remote Interface Operation: Set the flow control parameters using the

following 3488 command. This example assume a digital I/O module

is installed in slot 4.

OUTPUT 709; “DMODE 4,1,0,1”

! Set the flow control to Mode

#1 and the polarity of all

lines to default values.

About Flow Control Modes (Handshake)

Five flow control modes are available for Digital I/O operations. Some

modes use one or more of the three flow control lines: I/O Direction,

PFLG, and PCTL. Select the flow control you need for your digital input/

output applications.

Note The polarity of the flow control lines is assumed to be positive (the

default) in the following diagrams and discussions.

Mode

Number

Handshake

Mode

Definition

Notes

1 Static mode #1 Default handshake mode.

2 Static mode #2 Read what was written.

3 Read or Write

and strobe

If you set a port to this mode, you cannot use

the port in a scan list.

4 Read and write

strobe

If you set a port to this mode, you cannot use

the port in a scan list.

5 Full handshake If you set a port to this mode, you cannot use

the port in a scan list.