SH7261 datasheet(1028/1348 Pages) RENESAS

1028 / 1348 page

Section 21 CD-ROM Decoder (ROM-DEC)

Rev. 2.00 Sep. 07, 2007 Page 996 of 1312

REJ09B0320-0200

(1)

Automatic Sync Maintenance Mode

In automatic sync maintenance mode, the sync code is ignored if detected within the one-sector

(2352-byte) period. Furthermore, if a sync code is not detected at the point where a next sector

should start, sync code maintenance is applied. If synchronization timing has changed, re-

synchronization is performed at the point where a sync code is detected within 2352 bytes after the

change.

Therefore, this mode is effective in rejecting abnormal sync patterns and following changes in

synchronization timing. Note, however, that this mode cannot achieve synchronization with the

first sector after a change to the synchronization timing.

Figure 21.8 shows operation in the case of normal sync-code detection, figure 21.9 shows a case

where a sync code is detected before a current one-sector period has elapsed, and figure 21.10

shows the case where the actual sync code is only detected some time after a full one-sector period

has elapsed.

Input data

Sync code

detection

Output data

Sector 1

Sector 2

Sector 3

Sector 4

Sector 6

Sector 2

Sector 3

Sector 4

Sector 5

Sector 6

Figure 21.8 Operation in Automatic Sync Maintenance Mode (Normal Timing)

Intput data

Sync code

detection

Output data

Sector 1

Abnormal sector

Abnormal

sector

Ignore

Maintain Ignore

Maintain

Re-synchronization

Abnormal

sector

Abnormal

sector

Sector 1

Sector 5

Sector 3

Sector 4

Sector 5

Sector 6

Figure 21.9 Operation in Automatic Sync Maintenance Mode

(When an Abnormally Short Sector is Encountered)

SH7261 Datasheet(PDF) 1028 Page - Renesas Technology Corp

SH7261 Datasheet(HTML) 1028 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL