Keithley 2635 Reference Manual

D-24 Return to Section Topics 2600S-901-01 Rev. C / January 2008
Appendix D: Status Model Series 2600 System SourceMeter® Instruments Reference Manual
Measurement Event Registers
As shown in Figure D-5, there are seven register sets associated with Measurement Event Status.
Commands are summarized in Table D-9. Keep in mind that bits can also be set by using numeric
parameter values. For details, see “"Programming enable and transition registers"” in this
appendix.
For example, either of the following commands will set the VOLTAGE_LIMIT enable bit:
status.measurement.enable = status.measurement.VOLTAGE_LIMIT
status.measurement.enable = 1
When reading a register, a numeric value is returned. The binary equivalent of this value indicates
which bits in the register are set. For details, see “
"Reading registers"” in this appendix. For
example, the following command will read the measurement enable register:
print(status.measurement.enable)
The bits used in the Measurement Event Registers are described as follows:
• Bit B0, Voltage Limit (VLMT) — Set bit indicates that the voltage limit was exceeded. This
bit will be updated only when (1) a measurement is taken or (2) the
smuX.source.compliance command is invoked.
• Bit B1, Current Limit (ILMT) — Set bit indicates that the current limit was exceeded. This
bit will be updated only when (1) a measurement is taken or (2) the
smuX.source.compliance command is invoked.
• Bit B7, Reading Overflow (ROF) — Set bit indicates that an overflow reading has been
detected.
• Bit B8, Buffer Available (BAV) — Set bit indicates that there is at least one reading stored
in either or both of the non-volatile reading buffers.
• Bit B11, Output Enable (OE) — Set bit indicates that output enable has been asserted.
• Bit B13, Instrument Summary (INST) — Set bit indicates that a bit in the measurement
instrument summary register is set.
Measurement Event Current Limit Summary
This summary register set feeds to ILMT bit B1 of the Measurement Event Register. Used
summary bits for this register include B1 (SMUA) and B2 (SMUB). A set bit indicates that a SMU
(A or B) is in current limit (compliance).
Measurement Event Voltage Limit Summary
This summary register set feeds to VLMT bit B0 of the Measurement Event Register. Used
summary bits for this register include B1 (SMUA) and B2 (SMUB). A set bit indicates that a SMU
(A or B) is in voltage limit (compliance).
print(status.questionable.unstable_output.event)
1. * = '.ntr', '.ptr' and '.enable'; smuX = smua or smub.
Table D-8 (continued)
Operation event commands
Command
1
Bit

Keithley 2635 Specifications

General

Brand	Keithley
Model	2635
Category	Measuring Instruments
Language	English