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SD-PX15H
2 – 9
7. CD-ROM Write Mode
7.1. Outline
DVD-ROM can be upgraded from CD-ROM. The write mode is
entered from the normal mode.
entered from the normal mode.
1. When any CD-ROM for version upgrade DVD is detected, the sta-
tus informs that the version upgrade ROM is being read.
When DVD microcomputer is changed to System microcomputer
and byte 24 status data detects 0Fh:
and byte 24 status data detects 0Fh:
• The TEST Mode is entered by the status reception. (Required to
be internally recognized.)
• The Power button /Function switching is prohibited.
(Power supply is necessary until write is completed.)
• It is prohibited to accept any button input until write is com-
pleted.
• Change the display as follows:
Upper 5 x 7 dots: ROM_
Lower 5 x 7 dots: READING_
2. To expand into RAM, DVD performs read-operation.
3. When reading ends, transmission stops for writing.
(Ignore stoppage of transmission during write.)
When transmission stops, the transmission port receives write
states, which are displayed according to port states.
states, which are displayed according to port states.
Upper display section: ROM_
Lower display section: W: ***_
4. To open the DVD/CD door when end of rewrite is detected.
(The DVD status is not relevant since there is no communication.)
5. To close the DVD/CD door, cancel the TEST Mode and reset when
the Power button is pressed.
[4] Description on the Circuits of the 1-Bit
Unit (See the wiring diagrams on pages 6-
24 - 6-25.)
Unit (See the wiring diagrams on pages 6-
24 - 6-25.)
1. Input Part
Signals input from BIA102 are input to the AD conversion IC (ICA101,
ICA201 and ICA301) coupled by “CA101, CA102, CA201, CA202,
CA301 and CA302.
ICA201 and ICA301) coupled by “CA101, CA102, CA201, CA202,
CA301 and CA302.
2.
Modulation 1-Bit Converter
Signals input to the AD conversion ICs (ICA101, ICA201 and ICA301)
are converted into 1-bit signals for differential output. For detailed
description of the conversion into 1-bit signals, refer to the Technical
Manual for SM-SX100 already published.
are converted into 1-bit signals for differential output. For detailed
description of the conversion into 1-bit signals, refer to the Technical
Manual for SM-SX100 already published.
3. Low Pass Filter Circuit
The 1-bit signals switched at the output ICs (ICA102, ICA202 and
ICA302) are converted into analog signals by passing through the low
pass filter consisting of LA104 to LA104, LA201 to LA204 and LA301
to LA304.
ICA302) are converted into analog signals by passing through the low
pass filter consisting of LA104 to LA104, LA201 to LA204 and LA301
to LA304.
The property of low pass filter is flat up to 20 kHz and attenuated at
approx. 40 kHz by approx. 3 dB.
approx. 40 kHz by approx. 3 dB.
4. Dynamic Feedback Circuit
The 1-bit signals switched at the output ICs (ICA102, ICA202 and
ICA302) are amplified between plus power and GND.
ICA302) are amplified between plus power and GND.
By resistive division, the 1-bit signals pass through 75 k
Ω of NF resis-
tance (RA111 to RA114, RA211 to RA214, RA311 to RA314) and are
fed back to the AD conversion IC (ICA101, ICA201 and ICA301). P-P
voltage at this time is approx. 5 V.
fed back to the AD conversion IC (ICA101, ICA201 and ICA301). P-P
voltage at this time is approx. 5 V.
DVD DATA
DVD CLK
State
Unit display
1
L
H
—
No display
2
H
L
During write
W : S T R
3
H
H
Write ended
W : E N D
4
L
L
Write error
W : E R R
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