MN66279RSC Datasheet, PDF (63/96 Pages) Panasonic Semiconductor – LSI FOR COMPACT DISC/CD ROM PLAYER

MN662790RSC
When SSELʹH: (When microcomputer command 000847h is input)
BLKCK
CLDCK
SQCK
SUBQ
CRC
Q8 Q7 Q6 Q5 Q4 Q3 Q2 Q1 ^{Q16 Q15}
Q73 L8
R15 _CRC
CRC
STAT
(=CRC)
H: CRC=OK ɹɹɹɹ ɹɹ L: CRC=NG


H: CRC=OK ɹɹɹɹ ɹɹ L: CRC=NG
DEMPH
SQOK
8.7 ms
B. Read subcode data
By inputting a clock from SBCK pin, subcode data, P to W, can be read from SUBC pin. The timing is
shown in Figure 7-2-5.
Since subcode data varies every falling edge of CLDCK, input 8 clocks of SBCK every falling edge of
CLDCK, and switch the content of SUBC output to P to W.
Then you should receive SUBC output which varies in synchronization with the falling edge of SBCK at the
timing of the rising edge of SBCK. You can read all subcode data by repeating the operation above for each
CLDCK.
By inputting SBCK, the content of FLAG output will change. So you cannot measure the error rate when
reading subcode. You must consider it in system designing.
Use of SQOK Signal
Usually the BLKCK signal is used as a trigger to start reading SUBQ data.
The data is output from the SUBQ pin in synchronization with the SQCK signal. The necessary bits of data
(i.e., usually 80 bits) need to be read before the next BLKCK signal output is turned on.
The SQOK signal is set to H level for approximately 8.7 ms in the first half of the BLKCK-synchronous
period. There is no need to finish reading the data while the SQOK is at H level.
The SQOK signal is used for reading SUBQ data without using BLKCK interruption. The SQCK signal is
monitored by software scanning and the reading of SUBQ data is started on detection of the H-level signal.
At that time, the data must be read for a maximum approx. 2 ms because the period until the next BLKCK
signal output is turned on is approx. 4.6 ms.
SDD00025AEM
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