User's Manual

Using the Matrix Modules 39Chapter 3

Scanning Channels

Scanning matrix module channels consists of closing a sequence of

channels one channel at a time. Single scan, multiple scans, or continuous

scanning modes are available. TRIGger:SOURce specifies the source to

advance the scan. OUTPut can be used to enable the E1406A Command

Module Trig Out port or TTL Trigger bus lines (0-7).

Example: Scanning

Channels Using

TTL Triggers

(BASIC)

This example uses the E1406A Command Module TTL Trigger Bus Lines

to synchronize matrix module channel closures to an E1412A system

multimeter. For measurement synchronization, the E1406A TTL Trigger

Bus Line 0 is used by the matrix module to trigger the multimeter to perform

a measurement. The E1406A TTL Trigger Bus Line 1 is used by the

multimeter to advance the matrix module channel scan.

Note that these trigger bus lines are not actual hardware connections.

Triggering is accomplished by the E1406A firmware. Row 00 (High and Low)

of an E1465A 16x 6 matrix module is connected to the voltmeter's High and

Low. The columns are then scanned, switching in different DUTs (devices

under test).

Figure 3-1 shows how to connect the matrix module to the multimeter

module. The connections shown with dotted lines are not actual hardware

connections, but indicate how the firmware operates to accomplish the

triggering.

Figure 3-1. Example: Scanning Using TTL Triggers

E1406A

Command Module

Multimeter Module

E1412A

E1466A

Terminal Module

Matrix Module

E1466A

Row 00H

Row 00L

Complete

Trigger

TTLTrg1

TTLTrg0

TTLTrg1

TTLTrg0