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| Power ON Mechanical Sequence – DVD Disc | |
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| Operation | Purpose |
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1. | Power On button is pressed. | IC202 retrieves start up program from Flash ROM IC205. After the |
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| ICs are checked for basic communications, IC202 instructs Servo |
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| IC701 to start the mechanical sequence. The servo parameters are |
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| stored in EEProm IC201. |
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2. | Disc tray is closed (if open) and placed into a | Clamps a disc on the spindle motor platform. |
| chucked position. |
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3. | Sled moves the optical assembly to home position. | Sled starting point. |
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4. | Tilt Motor resets laser platform to mid position. | Presets the laser beam perpendicular to the disc for max RF. |
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5. | Sled moves outward quickly then slows down. | Optical assembly is moving under the disc’s information area. |
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6. | Laser is turned ON momentarily during focus search. | Looks for a disc. Reflected light identifies a disc. |
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7. | Focus search one time. | Optical assembly lens moves up then down, counting the number of |
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| disc layers. |
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8. | Sled stops moving when a disc Is identified. |
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9. | Spindle motor rotates. | Rotates the disc. |
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10. Laser is turned ON a second time. | To begin playback. | |
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11. | Focus search. | Focuses on the first information layer on the disc. |
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12. | Focus servo is turned ON. | Maintains focus on the layer. |
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13. | Tracking begins. | Keeps the laser beam at the information track’s center. |
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14. | Tilt motor servo starts. | Maintains high RF level. |
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15. | Disc PB begins. Display shows elapsed time. | Playback verification. |
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