12
(20) Revision of the DVD mechanism controller
[M:
∗
.
∗∗∗
/
∗
.
∗∗∗
]
Revision number of the external ROM part (flash ROM) of the
DVD mechanism controller
<Front>
Revision of the internal ROM (core part) of the DVD mechanism
controller
<Rear>
(21) Version of the AV-1 chip [AV:
∗
.
∗
]
(22) Version of the FL controller [F:
∗
.
∗
]
(23) Control number of the GUI-ROM [GUI:
∗∗∗
]
(24) The part number of the flash ROM and system
controller [S :
∗∗∗∗∗∗
/
∗∗∗∗∗∗∗
]
Part number of the flash ROM
<Front>
(Example) VYW1602-A
→
W1602A
(Example) PD626A9
→
6256A9
Part number of the system controller
<Rear>
(Example) PD3381T1
→
3381T1
(25) Part number of the DVD mechanism controller
(Example) PD4889A0
→
4889A0
(26) AV1 classification [AV1 :
∗∗∗
]
RAM, E/A, S/C
(27) Flash ROM size [FLSH :
∗∗
]
8M : 8M bit, 4M : 4M bit
2.8 DESCRIPTIONS OF NEW FUNC-
TIONS IN TEST MODE
2.8.1 Error Rate
Overview
The error rate of CDs can be measured and the value is displayed in
decimal and indicates the number of C1 errors (including the
corrected ones) counted during the specified measurement time.
An indeterminate measurement result may be caused by a dirty disc,
decentering, surface deflection, birefringence (double reflection),
or a pickup problem (dirty lens, etc.), misadjustments of the pickup,
improper automatic adjustment, or incomplete adjustments. On the
manufacturing line, the value is used for yes/no decision of pickups.
Normally, for a measurement for 5 seconds, the value may be less
than 10 with a clean disc and less than 100 with a disc with some
damage.
Using the Function in Test Mode (The Remote
Control Keys to be Used are Indicated in Brackets)
(1) Set the CD to trace (playback) state.
(2) Set the player to Number input mode by pressing [+10] and
enter the measurement time in a range of 1 to 5 (sec.).
(3) Start measurement by pressing [TEST] + [0]. The SubQ counter
stops during measurement, but this is not a malfunction. When
the specified measurement time has elapsed, the result is
indicated to the right of “ER C1 –” on the screen.
If you skip step 2, the measurement time is set to 5 (sec).
2.8.2 Jitter Value
Overview
The jitter values of DVDs and CDs, which show a voltage in three-
digit decimal as .
V, can be displayed. For example, the indication
“0278” means 2.78 V. The larger the value, the worse the jitter.
The worst value is 3.25 V. When playing a DVD or a video CD
with which the jitter value is extremely high, mosaics may be seen.
As with the error rate, the jitter depends on the disc and pickup.
The jitter value to be displayed has no close correlation with a jitter
measuring device, and is to be regarded just for reference.
Reference : When the jitter value is 2.9 V or more with a DVD, or
3.0 V or more with a CD (or a video CD), it may cause
a problem (mosaic, audio distortion, etc.) in playback.
Using the Function in Test Mode (The Remote
Control Keys to be Used are Indicated in Brackets)
(1) Set the DVD or CD to trace (playback) state with AGC OFF.
(2) Press [TEST] and [DIGITAL/ANALOG].
The current jitter value appears to the right of “JT:
” on
the display. The jitter value keeps changing unless any additional
key operation is made.
Note : Although a value may be displayed on the screen even with
AGC ON, this is NOT a jitter value.
The jitter value with AFB ON cannot be displayed (see the
next section). The jitter value with AFB ON can be obtained
only by directly measuring the voltage at the JV connector
(pin 94) of the servo DSP (LC78650).
