Sound Test - Toshiba 650CT Maintenance Manual

3.15 Sound Test

To execute the sound test, select 12 from the DIAGNOSTICS TEST menu, press Enter and
follow the directions on the screen. The sound test contains four subtests that test the
computer's sound functions.
NOTE: To execute this subtest, the internal microphone and internal headphone (or
internal speaker) are required.
WARNING: The system is capable of producing high volume sound, so when you use
the headphones be careful to set the volume low and adjust it as necessary. Using the
headphones at full volume could damage your ears.
Subtest 01 CODEC (REC/PLAY)
This subtest tests the functions of the Codec (AD1848) A/D, D/A converter.
At the same time, it tests the microphone terminals and headphone terminals.
When you execute this subtest the following message is displayed:
[Quick REC & PLAY for AD1848]
Press any key to *** REC ***
After pressing any key, start recording, then immediately play the sound. (It
takes three seconds.)
Subtest 02 FM Synthesizer
This subtest tests the OPL# (YMF262) functions. Connect the headphone,
then check the scale on the right and left sides. Also check the sound adjust-
ment volume.
Subtest 03 SIN wave playback
This subtest expands the sine wave data table to 64KB and creates sine wave
data. The play data is transferred between DMA and CODEC, and plays the
sound. (It is a long beep.) Also, using the oscilloscope, observe the sine
waveform.
Subtest 04 CODEC (line in/out) (record sound/replay)
Load the file AD1848L.COM. Connect a sound source such as a CD player or
stereo to the line-in port.
After making the connections, a dialog box will display. Press Enter to play a
recorded sound. About three seconds after the recorded sound is played, the
dialog box will display again.
650CT
3-31