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Measurement Computing Isolator488 User Manual

Page 29

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Section 3

IEEE 488 Primer

3-8

3.7.2 Listen Address Group (LAG)

There are 31 (0 to 30) listen addresses associated with this group.

The 3 most significant bits of the data bus are set to 001 while the 5 least
significant bits are the address of the device being told to listen.

3.7.3 Unlisten (UNL)

This command tells all bus devices to Unlisten. The same as

Unaddressed to Listen. ($3F)

3.7.4 Talk Address Group (TAG)

There are 31 (0 to 30) talk addresses associated with this group.

The 3 most significant bits of the data bus are set to 010 while the 5 least
significant bits are the address of the device being told to talk.

3.7.5 Untalk (UNT)

This command tells bus devices to Untalk. The same as

Unaddressed to Talk. ($5F)

3.7.6 Local Lockout (LLO)

Issuing the LLO command prevents manual control of the

instrument's functions. ($11)

3.7.7 Device Clear (DCL)

This command causes all bus devices to be initialized to a pre-

defined or power up state. ($14)