Non-Volatile Memory; Liquid Crystal Display (Lcd); Screen Display - Olympus OEP-3 Service Manual

Nonvolatile memory
Each menu setting or caption character string is stored in IC220 (NH58V66APF-10Z). Data is read from
the nonvolatile memory when the system starts.
Data [COLOR LOAD] and [USER LOAD] are also stored in IC220.
LED
The PRINT LED (that lights during printing) is controlled in lighting by Q170. A control signal is output
from CPU (pin 94 of IC100). The ALARM LED (that lights when an error occurs in a printer) is
controlled in lighting by Q171. A control signal is output from CPU (pin 95 of IC100).
Buzzer
A buzzer sound pulse is output from CPU (pin 98 of IC100) and driven using a circuit consisting of
Q180, R180, and R181. The buzzer does not sound when [BEEP:OFF] is set in the menu.
Liquid-crystal display (LCD)
The bus control of LCD is performed using general-purpose logic groups IC230 and IC4xx. The display
density of LCD is controlled by IC300, Q160, R160 to R163, and C160. The control signal (analog
voltage value) is output from CPU (pin 85 of IC100) as an analog signal. No display may appear on the
LCD when [LCD-CONT:OFF] is set in the menu.

Screen display

A screen display control signal is generated by IC150. The clock of IC150 is generated using an
oscillator circuit that incorporates C150, C151, L150, and IC150. The OSD HD and OSD VD signal
inputs from the VPR board are required as a timing pulse. The control signal of display data is output
from CPU (pins 23 to 25 of IC100). Characters are actually superimposed using an analog switch on the
VPR-63 board. No screen display may appear when [SOURCE:THRU] or [DISPLAY:OFF] is set in the
menu.
Input of main unit's key (main key/operation key)
The state of the main unit's key is processed by IC270, R270 to R277, and R820 to R827 and input
through a data bus to CPU. The timing pulse of a data input signal is output by a circuit consisting of
IC110, D110 to D113, and R110 to R113.
Remote 1 input and infrared remote control reception
An infrared remote control pulse is received using the infrared photosensor in a main key block. The
pulse from the main key is waveform-shaped by IC301 on the SY-282 board and once output to the IF-
767 board. If a wired remote control is connected to the IF-767 board, a wired remote control pulse is
input to the SY-282 board. If it is not connected, the output pulse of a photosensor is input to the SY-282
board. Since a pulse is switched by J1 on the IF-767 board, the wire remote control operation may fail
due to the failure of J1. The pulse from the IF-767 board is waveform-shaped by IC301 on the SY-282
board and input to CPU (pins 99 and 100 of IC100).
Remote 2 input
There are a digital-type remote control (RM-91) and analog-type remote control (FS-36) in J2 on the IF-
767 board. The two types of remote controls can be connected. A digital-type signal is processed by
IC302 and input to CPU (pin 88 of IC100). An analog-type signal is processed by IC300 and input to
CPU (pin 84 of IC100).
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OEP-3 V1 (UC)