Self-Test And Diagnostics - Tektronix SCD1000 Service Manual

General Operating Instructions
Self-Test and
Diagnostics
2-14
The SCD Waveform Recorders perform intemal self-test routines each time the
instrument is powered up. The power-up self-test can be bypassed by setting
the rear-panel PWR UP TEST switch OFF. Power-up self-test routines require
no user interaction.
. NOTE
Instrument warm-up can take 20 minutes.
If any test fails, the following occur:
• the instrument attempts to run while reporting an Internal Error event code
over the GPIB
• the front-panel FAULT indicator (beneath the Display Unit) lights to indicate
a fault
• A descriptive message is displayed in the Message/Measurements Zone
of the Display Unit
The power-up self-test consists of the Kemel Tests and the Essential Diagnos-
tics Tests. Kernel tests include the microprocessor, processor RAM and ROM,
and the GPIB communication system tests. These tests verify that all the
resources needed by the operating system are working. Once the kernel tests
have passed, the operating system is activated.
. i
The first task of the operating system is to execute the Essential Diagnostics
J
tests, which assure that all basic subsystems properly function. No kemel or
essential diagnostics are performed with Power-up test off.
Self-test can also be initiated over the GPIB (using the TEST command) or .
from the Display Unit. See Section 6 of the
SCD1000/SCD5000 Operator
Manual
more information on the TEST command.
The SCD Waveform Recorders also provide calibration routines for the follow-
ing subsystems. These routines are only initiated from the Display Unit or over
the GPIB, and are not part of the power-on sequence.
• CALIBRATE HORIZONTAL: Performs self-calibration of the horizontal
sweep circuits.
• CALIBRATE TRIGGER: Performs self-calibration of trigger circuits.
• CALIBRATE VERT: Performs self-calibration of Gain and Offset vertical
circuits.
• CALIBRATE CRT: Performs self-calibration of the CRT circuits.
• CALIBRATE ALL: Executes all calibration routines.
Refer to Section 6 of the
SCD1000ISCD5000 Operator Manual
for more infor-
mation on the CALIBRATE command.
Operating Information