Agilent Technologies 3458A User Manual

SPOLL (Serial Poll)
306 Appendix B GPIB Commands
Examples REMOTE 7 !SETS GPIB REN LINE TRUE
The above line does not, by itself, place the multimeter in the remote state. The
multimeter will only go into the remote state when it receives its listen address
(e.g., sending OUTPUT 722;"BEEP").
REMOTE 722 !SETS REN LINE TRUE AND ADDRESSES DEVICE 22
The above line places the multimeter in the remote state.
SPOLL (Serial Poll)
The SPOLL command, like the STB? command (multimeter command set),
returns a number representing the set bits in the status register (status byte). The
returned number is the weighted sum of all set bits.
Syntax P=SPOLL (722)
Status Register Bits The bits and their corresponding weights are:
Remarks • If the SRQ line is set true when you send SPOLL, all bits in the status register
are cleared provided the condition that set. the bit(s) is no longer present. If the
SRQ line is false when you send SPOLL, the status register's contents are not
changed.
• The SPOLL command differs from the STB? command in that STB? interrupts
the multimeter's microprocessor. Thus, with STB? the multimeter always
appears to be busy (bit 4 clear). SPOLL simply extracts the status byte without
interrupting the microprocessor. Therefore, you can use SPOLL to monitor the
readiness of the multimeter for further instructions.
• If data is in the output buffer when you send the SPOLL command, that data
remains intact. If data is in the output buffer when you send the STB? command,
however, the data is replaced by the status data.
Examples 10 P=SPOLL (722) !SENDS SERIAL POLL, PLACES RESPONSE INTO P
20 DISP P !DISPLAYS RESPONSE
30 END
Bit
Number
Decimal
Weight Description
0 1 Subprogram execution completed
1 2 Hi or lo limit exceeded
2 4 SRQ command executed
3 8 Power - on SRQ occurred
4 16 Ready for Instructions
5 32 Error (consult error register)
6 64 Service requested
7 128 Data available

Agilent Technologies 3458A Specifications

General

Model	3458A
Manufacturer	Agilent Technologies
Category	Multimeter
Digits	8.5
Sampling Rate	100, 000 readings/second
Interface	GPIB

Summary

Safety Symbols and Warnings

General Safety Precautions (WARNINGS)

Outlines essential safety precautions for operating, servicing, and repairing the product to prevent injury or damage.

Chapter 2 Getting Started

Operating from the Front Panel

Covers using front panel keys, making measurements, changing functions, and controlling display settings.

Operating from Remote

Explains how to control the multimeter remotely via GPIB, including address management and command sending.

Chapter 3 Configuring for Measurements

General Configuration

Configuring for DC or Resistance Measurements

Details how to configure the multimeter for DC voltage, DC current, and 2-wire or 4-wire resistance measurements.

Configuring for AC Measurements

Explains how to configure the multimeter for AC voltage, AC current, frequency, or period measurements.

Chapter 4 Making Measurements

Triggering Measurements

Explains the three-event triggering hierarchy (arm, trigger, sample) and various event choices.

Using Reading Memory

Sending Readings Across the Bus

Increasing the Reading Rate

Discusses the multimeter's high-speed mode and factors affecting reading rate and transfer speed.

Math Operations

Explains real-time and post-process math operations, enabling/disabling them, and math registers.

Chapter 5 Digitizing

Digitizing Methods

Details DCV, Direct-Sampling, and Sub-sampling methods, summarizing their characteristics and signal paths.

The Sampling Rate

Level Triggering

Describes how to specify voltage and slope for sampling initiation, with examples for DCV and direct-sampling.

DCV Digitizing

Direct-Sampling

Explains direct-sampling using track-and-hold, its bandwidth, and specifying ranges via max._input parameter.

Sub-Sampling

Covers sub-sampling fundamentals, advantages, and how to specify effective interval and number of samples.

Chapter 6 Command Reference

ACAL

Instructs the multimeter to perform self-calibrations (ALL, DCV, AC, OHMS) and discusses autocalibration security.

NRDGS

OFORMAT

PRESET

Configures the multimeter to one of three predefined states: NORM, FAST, or DIG for different operation modes.

SUB

Stores a series of commands as a subprogram, assigning a name for later execution.

TARM

Defines the trigger arm event to enable the trigger event and can be used for multiple measurement cycles.

TEST

Causes the multimeter to perform a series of internal self-tests to check hardware and software integrity.

TRIG

Specifies the trigger event that initiates a measurement, working with TARM and NRDGS.

Chapter 7 BASIC Language for the 3458A

BASIC Language Commands

Subprograms

Explains how to store, execute, and manage BASIC language subprograms for system control and automation.

Appendix B GPIB Commands

TRIGGER (GET)

Appendix C Procedure to Lock Out Front/Rear Terminals and Guard Terminal Switches

Procedure

Outlines the steps for installing the switch lockout kit, including covers and pushrod removal.

Appendix D Optimizing Throughout and Reading Rate

Maximizing the Testing Speed

Covers strategies like tailoring communication paths, program memory, and state storage for optimal testing speed.

DC Volts, DC Current and Resistance

Explains the measurement paths (DCV, track-and-hold) and trade-offs for DC measurements.

AC Volts and AC Current

Details the three ACV measurement techniques (Analog, Synchronous, Random) and their trade-offs.

Frequency and Period

Optimizing the Testing Process Through Task Allocation

Discusses allocating tasks between the DMM and computer using math functions, memory, and program structure.

Math Operations

State Storage and Program Memory

A Benchmark

Appendix E High Resolution Digitizing With the 3458A

Speed with Resolution

Details the multimeter's flexibility in speed and resolution for audio frequency bandwidth.

Digitizing Analog Signals

Avoiding Aliasing

Provides methods to avoid signal distortion caused by aliasing, ensuring accurate waveform representation.

Choice of Two Measurement Paths

Describes the standard DCV path and the track-and-hold path for digitizing and sampling.

Capturing the Data

High Speed Data Transfers

Errors in Measurements