Keithley 617 User Manual

REMOTE 727 (END LINE)
S = SI’OLL(727) (END LINE)
DISP S (END LINE)
When the END LINE key is pressed the second time, the com-
puter conducts the serial polling sequence. The decimal value
of the status byte is then displayed on the computer CRT
when the END LINE key is pressed the third time. More infor-
mation on the status byte may be found in paragraph 3.10.15.
Model 8573 Programming Example-Use the following
sequence to serial poll the instrument and display the decimal
value of the status byte on the computer CRT:
V%=l:CALL IBSRE(BRDO%,V%) (return)
CALL IBRSP(M617%,SB%) (return)
PRINT SB% (return)
When the return key is pressed the second time, the serial
polling sequence is conducted. The status byte value is
displayed when the return key is pressed the third time.
3.10 DEVICE-DEPENDENT COMMAND
PROGRAMMING
IEEE-488 device-dependent commands are used with the
Model 617 to control various operating modes such as func-
tion, range, trigger mode, and data format. Each command is
made up of a single ASCII letter followed by a number
representing an option of that command. For example, a
command to control the measuring function (Volts, Ohms,
Amps, Coul) is programmed by sending an ASCII “F” follow-
ed by a number representing the function option. The
IEEE-488 bus actually treats these commands as data in that
ATN is false when the commands are transmitted.
A number of commands may be grouped together in one str-
ing. A command string is usually terminated with an ASCII
“X” character, which tells the instrument to execute the corn-
mand string. Commands sent without the execute character
will not be executed at that time, but they will be retained
within an internal command buffer for execution at the time
the X character is received. If any errors occur, the instrument
will display appropriate front panel error messages and
generate an SRQ if programmed to do so.
Commands that affect the electrometer section (F, R, C, Z, N,
T, and A) will trigger a reading when the command is ex-
ecuted. These bus commands affect the Model 617 much like
the front panel controls. Note that commands are not
necessarily executed in the order received; instead, they will
be executed in the same order as they appear in the status
word:
Function (F); Range (R); Zero Check (C); Zero Correct (Z);
Suppress (N); Trigger(T); Voltage Source Operate (0): Read
Mode (B); Display Mode (D): Data Storage (Q): SRQ Mode
CM): EOI and Bus Hold-off (K); and Terminator (Y). Thus to
force a particular command sequence, you would follow each
command with the execute character, as in the example str-
ing, ClXZlXCOX, which can be used to zero correct the in-
strument.
These programming aspects are covered at the end of this
paragraph.
Device-dependent commands can be sent either one at a time,
or in groups of several commands within a single string.
Some examples of valid command strings include:
FOX Single command string.
FOKlDOROX Multiple command string.
T6 X Spaces are ignored.
Typical invalid command strings include:
HlX Invalid command, as H is not one of the instrument
commands.
F9X Invalid command option because 9 is not an option of
the F command.
If an illegal command (IDDC), illegal command option UDD-
CO), is sent, or if a command string is sent with REN false,
the string will be ignored.
Devicedependent commands that control the Model 617 are
listed in Table 3-11. These commands are covered in detail in
the following paragraphs. The associated programming ex-
amples show how to send the commands with both the HP-85
and the IBM-IW8573.
NOTE
Programming examples assume that the Model
617 is at its factory default value of 27.
In order to send a devicedependent command, the controller
must perform the following steps:
1. Set ATN true.
2. Address the Model 617 to listen.
3. Set ATN false.
4. Send the command string cwer the bus one byte at a time.
317

Keithley 617 Specifications

General

Brand	Keithley
Model	617
Category	Measuring Instruments
Language	English

Summary

Warranty Information

Warranty

Details the warranty terms and conditions for the product and specific components.

Specifications

Specifications

Details the electrical and performance specifications for the Model 617 electrometer.

Safety Precautions

Safety Precautions

Advises on essential safety measures to avoid injury and instrument damage during operation.

Section 1: General Information (Continued)

Unpacking and Getting Started

Details unpacking, inspection, and initial steps to operate the Model 617.

Section 2: Operation

2.2 Power Up Procedure

Details the steps for connecting power and turning on the instrument.

2.3 Power Up Self Test and Display Messages

Explains the self-test routine and potential display messages upon startup.

Section 2: Operation (Continued)

2.4 Front Panel Familiarization

Provides an overview of the Model 617's front panel layout, controls, and indicators.

2.7 Basic Measurement Techniques

Introduces fundamental procedures for making voltage, resistance, charge, and current measurements.

2.7.2 Input Connections

Details how to connect input signals to the rear panel INPUT connector.

2.7.4 Guarded Operation

Explains the concept and application of guarding to minimize leakage and improve measurements.

2.7.5 Making Current Measurements

Details the procedure for measuring low-level currents, including picoampere ranges.

2.7.6 Making Charge Measurements

Describes how to measure charge using the Model 617's coulombs ranges.

2.7.7 Resistance Measurements

Explains how to measure resistance using constant current and voltage methods.

2.8 Using The Voltage Source

Explains how to use the Model 617's built-in voltage source for V/I measurements.

2.10 Using External Feedback

Explains how to extend capabilities using external feedback networks.

2.11 Using Zero Correct and Baseline Suppression

Covers instrument offset cancellation and baseline value storage.

2.11.2 Using Suppression

Details how to store an offset value and subtract it from subsequent readings.

2.13 External Triggering

Explains how to trigger the instrument using external BNC connectors.

2.4.1 Controls

Describes the function and operation of each front panel control button.

2.5.3 Calibration

Introduces the digital calibration program for front panel or IEEE-488 bus use.

2.7.3 Making Voltage Measurements

Provides step-by-step instructions for measuring DC voltages with the Model 617.

2.8.1 Basic Operating Procedure

Guides on connecting and adjusting the voltage source output.

2.11.1 Zero Correct and Zero Check

Explains how to use Zero Correct and Zero Check to cancel internal offsets.

2.12 Data Storage

Describes the internal 100-point data store mode for logging readings.

2.13.1 External Trigger

Details continuous and one-shot triggering modes via the external trigger input.

2.14 Measurement Considerations

Discusses factors affecting measurements at low signal levels.

2.8.2 V/I Resistance Measurements

Describes how to measure high resistances using the voltage source and electrometer.

Section 3: IEEE-488 Programming

Section 3: IEEE-488 Programming (Continued)

3.4 Bus Commands

Covers device commands, grouped into uniline, multiline, and device-dependent categories.

3.7.2 Bus Connections

Details how to connect the Model 617 to the IEEE-488 bus using appropriate cables.

3.7.3 Primary Address Programming

Explains how to check and set the instrument's primary address for bus communication.

3.8 Software Considerations

Discusses software aspects for IEEE-488 controllers like HP-85 and IBM-PC.

3.9 General Bus Command Programming

Covers general bus commands like DCL, REN, IFC, LLO, GTL, SDC, GET, SPE, SPD.

3.10 Device-Dependent Command Programming

Details commands controlling modes like function, range, trigger, and data format.

3.10.2 Function (F)

Describes commands to select measurement functions like Volts, Amps, Ohms, Coulombs.

3.10.3 Range (R)

Explains commands for controlling instrument sensitivity and selecting measurement ranges.

3.10.4 Zero Correct and Zero Check (Z and C)

Details commands for canceling internal offsets and zeroing the instrument.

3.10.5 Baseline Suppression (N)

Explains commands to store an offset and subtract it from subsequent readings.

3.10.9 Voltage Source Value (V)

Details commands for programming the built-in voltage source output.

3.10.10 Voltage Source Operate (O)

3.10.12 Non-Volatile Memory Storage (L)

3.10.14 Trigger Mode (T)

3.10.15 SRQ Mask (M) and Status Byte Format

3.11.2 Number Error

3.4.5 Device-Dependent Commands

Describes commands specific to device configuration, controlling functions like mode and range.

3.10.8 Data Store Mode

Explains how to use the data store for logging readings and setting intervals.

3.10.11 Calibration Value (A)

Describes commands for setting calibration values for ranges and functions.

3.10.18 Status (U)

3.11.1 Bus Error

Section 4: Applications

4.2 Insulation Resistance Measurements

Details how to measure high insulation resistances using constant current and voltage methods.

Section 4: Applications (Continued)

4.3 High Impedance Voltmeter

Explains using the Model 617 as a high-impedance voltmeter with minimal circuit loading.

4.5 Diode Characterization

4.6 Capacitor Leakage Measurements

4.4 Low-Level Leakage Current Measurements

Guides on measuring low-level currents like nanoamperes and picoamperes.

4.7 Capacitance Measurement

4.10 Using The Model 617 With External Voltage Sources

Section 5: Performance Verification

Section 5: Performance Verification (Continued)

5.5 Verification Procedures

Provides detailed procedures for verifying accuracy of volts, ohms, amps, and coulombs functions.

5.5.3 Coulombs Verification

5.5.4 Volts Verification

5.5.5 Ohms Verification (2kΩ–20MΩ Ranges)

5.5.7 Voltage Source Verification

5.5.1 Input Current Verification

5.5.6 Ohms Verification (200MΩ and GΩ Ranges)

5.5.2 Amps Verification

Section 7: Maintenance

7.2 Line Voltage Selection

Section 7: Maintenance (Continued)

7.3 Fuse Replacement

7.4.5 Front Panel Calibration

Provides step-by-step instructions for calibrating from the front panel.

7.4.7 Calibration Sequence

7.4.11 Amps Calibration

Provides calibration steps for the amps function across various ranges.

7.4.12 Coulombs Calibration

Details the procedure for calibrating the coulombs function.

7.4.14 Ohms Calibration

Provides calibration steps for the ohms function across various ranges.

7.4.15 Voltage Source Calibration

Details the procedure for calibrating the instrument's internal voltage source.

7.6 Disassembly Instructions

7.7.2 Power Up Self Test

7.7.7 A/D Converter and Display

7.7.8 Input and Ranging Amplifiers

7.4 Calibration

Introduces digital calibration capabilities and recommendations.

7.4.6 IEEE-488 Bus Calibration

Details procedures for calibrating the instrument via the IEEE-488 bus using a computer.

7.4.8 Input Offset Adjustment

Describes steps to null any small offset in the input amplifier.

7.4.13 Volts Calibration

Outlines the calibration steps for the volts function across different ranges.

7.7 Troubleshooting

Offers guidance for diagnosing and resolving instrument problems.

7.7.3 Self Diagnostic Program

7.4.9 Input Current Adjustment

Details procedures to null input current in the input stage for temperature compensation.

7.4.10 Permanent Storage of Calibration Parameters