14
X-EM21V
1
2
3
4
A
B
C
D
E
F
1
2
3
4
[2] Operations with a USB memory device not possible
1. Can the device information be displayed?
Check Pins
8
0 and 79 of U901 or check the
peripheries of Pins 12, 13 and 5. (See Figs. 6 and 7.)
2. When a 1-kHz signal is played, are the
waveforms indicated in Fig.
8
output from
Pins 65 and 66 of U901?
USB system check
"NO USB" is displayed.
1. Check power from U901 (SPHE
8
202RQ-D) and XP906.
2. Check the communication line between IC701 (CA6
8
17) and U901 (SPHE
8
202RQ-D).
[3] Data in a USB memory device cannot be played.
Data in the USB memory device cannot be played even if the USB operation key is pressed.
1. Check the DP data line.
2. Check the DM data line.
Select the USB function, by pressing the I
N
PUT button on the main unit (USB button on the remote control unit),
then plug a USB memory device into the USB connector.
Yes
N
o
Replace the MAI
N
Assy.
Check Pins 65 and 66 of U901.
N
o
Replace the MAI
N
Assy.
3. Are the waveforms indicated in Fig.
8
output
from Pins 23 and 24 of IC504?
Yes
Check the periphery of IC504.
N
o
Replace the MAI
N
Assy.
4. Are the waveforms indicated in Fig.
8
output
from Pins 22 and 32 of IC302?
Yes
Check the peripheries of IC601.
(X-EM21
V
only)
N
o
Replace the MAI
N
Assy.
Replace the MAI
N
Assy.
5. If Yes, check the periphery of IC302.
Yes
7
U901 - pin
8
0 (DM)
V
: 2
V
/div. H: 500 ns/div.
8
U901 - pin 79 (DP)
V
: 2
V
/div. H: 500 ns/div.
Fig. 6 Waveform
7
8
5
U901 - pin 65, IC504 - pin 24, IC302 - pin 22 (Lch)
V
: 1
V
/div. H: 1 ms/div.
6
U901 - pin 66, IC504 - pin 23, IC302 - pin 32 (Rch)
V
: 1
V
/div. H: 1 ms/div.
Fig.
8
Waveform
5
6
9
U901 - pin 12 (D
V
D-TXD)
V
: 2
V
/div. H: 500
μ
s/div.
a
U901 - pin 11 (D
V
D_RXD)
V
: 2
V
/div. H: 500
μ
s/div.
b
U901 - pin 5 (URST#)
V
: 2
V
/div. H: 500
μ
s/div.
Fig. 7 Waveform
9
a
b
