
[AK4683] 
MS0427-E-02 
2007/04 
- 52 - 
■
 Q-subcode buffers 
The AK4683 has Q-subcode buffer for CD application. The AK4683 takes Q-subcode into registers by following 
conditions. 
1.
The sync word (S0,S1) is constructed at least 16 “0”s. 
2.
The start bit is “1”. 
3.
Those 7bits Q-W follows to the start bit. 
4.
The distance between two start bits are 8-16 bits. 
The QINT bit in the control register goes “1” when the new Q-subcode differs from old one, and goes “0” when QINT 
bit is read. 
1 
2 
3 
4 
5 
6 
S0 
0 
0 
0 
0 
0 
0 
S1 
0 
0 
0 
0 
0 
0 
S2 
1 
Q2 
R2 
S2 
T2
U2
S3 
1 
Q3 
R3 
S3 
T3
U3
: 
: 
: 
: 
: 
: 
: 
S97 
1 
Q97 R97 S97
T97
U97
S0 
0 
0 
0 
0 
0 
0 
S1 
0 
0 
0 
0 
0 
0 
S2 
1 
Q2 
R2 
S2 
T2
U2
S3 
1 
Q3 
R3 
S3 
T3
U3
: 
: 
: 
: 
: 
: 
: 
 (*) number of "0" : min=0; max=8. 
Figure 31. Configuration of U-bit(CD) 
Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 Q20 Q21 Q22 Q23 Q24 Q25
CTRL 
ADRS 
TRACK NUMBER 
Q26 Q27 Q28 Q29 Q30 Q31 Q32 Q33 Q34 Q35 Q36 Q37 Q38 Q39 Q40 Q41 Q42 Q43 Q44 Q45 Q46 Q47 Q48 Q49
MINUTE 
SECOND 
Q50 Q51 Q52 Q53 Q54 Q55 Q56 Q57 Q58 Q59 Q60 Q61 Q62 Q63 Q64 Q65 Q66 Q67 Q68 Q69 Q70 Q71 Q72 Q73
ZERO 
ABSOLUTE MINUTE 
Q74 Q75 Q76 Q77 Q78 Q79 Q80 Q81 Q82 Q83 Q84 Q85 Q86 Q87 Q88 Q89 Q90 Q91 Q92 Q93 Q94 Q95 Q96 Q97
ABSOLUTE FRAME 
Figure 32. Q-subcode 
Addr 
Register Name 
D7 
D6 
16H Q-subcode Address / Control 
Q9 
Q8 
17H Q-subcode Track 
Q17 
Q16 
18H Q-subcode Index 
··· 
···
19H Q-subcode Minute 
··· 
···
1AH Q-subcode Second 
··· 
···
1BH Q-subcode Frame 
··· 
···
1CH Q-subcode Zero 
··· 
···
1DH Q-subcode ABS Minute 
··· 
···
1EH Q-subcode ABS Second 
··· 
···
1FH Q-subcode ABS Frame 
Q81 
Q80 
Figure 33. Q-subcode register 
7 
0 
0 
V2
V3
: 
V97 W97
0 
0 
V2
V3
: 
8 
0 
0 
* 
0…
0…
0…
0…
: 
0…
0…
0…
0…
0…
: 
W2
W3
: 
0 
0 
W2
W3
: 
INDEX 
FRAME 
ABSOLUTE SECOND 
CRC 
G(x)=x
16
+x
12
+x
5
+1 
D5 
··· 
··· 
···
···
···
···
···
···
···
··· 
D4 
···
···
···
···
···
···
···
···
···
···
D3 
···
···
··· 
··· 
··· 
··· 
··· 
··· 
··· 
···
D2 
···
···
···
···
···
···
···
···
···
···
D1 
Q3 
Q11 
···
···
···
···
···
···
···
Q75 
D0 
Q2 
Q10
···
···
···
···
···
···
···
Q74
↑
Q