2. 2-byte Commands

The commands are executed on the falling edge of RWC.

Focus Servocontroller (pin 13: FOCS, pin 14: FST, pin 15: FZD and pin 57: LASER)

1. Laser Control

2. Focus Start

When a Focus Start command (either 1 or 2) is issued, the pickup lens is first lowered as C1 discharges through FST

and then raised gradually as C1 is recharged by FOCS. FZD goes low when the focal point is reached, and FOCS is

reset and the focus servocontroller turned on when this signal is received.

After issuing this command, the microprocessor checks the DRF signal from the LA9210 to verify that focus has

been reached, and advances to the next step. If C1 recharges fully before focus has been reached, the Focus Start

command should be reissued to repeat operation of the focus servocontroller.

No. 4521-9/23

LC78681E

MSB

LSB

Command

RES = low

00001000

FOCUS START #1

10100010

FOCUS START #2

00001010

LASER ON

10001010

LASER OFF

00000000

NOTHING