Samsung SF-4500 Service Manual page 56

6-2. OPE PBA
6-2-1. SUMMARY
OPE Board is separated functionally from the main
board and operated by the micom(Z8601) in the
board. OPE and the main use UART (universal asyn-
chronous receiver/transmitter) channel to exchange
information. OPE reset can be controlled by the main.
OPE micom controls key-scanning and LCD and
LED display, detects documents and
senses SCAN position. If there occurs an event in
OPE (such as key touch and sensor level change), it
sends specific codes to the main to respond to the sit-
uation and the main analyzes these codes and oper-
ates the system. For example, if the main is to display
messages in OPE, the main transmits data through
UART line to OPE according to the
designated format and OPE displays this on LCD,
LED. OPE's sensing is also transmitted to the main
through UART line and then the main drives
necessary operation.
Scan
Position
Sensor
Document
Detect
Sensor
Connector
Samsung Electronics
MICOM
Z8601
UART 2
Reset
Fig.6-2-1. OPE BLOCK DIAGRAM
6-2-2 OPE Circuit
OPE PBA consists of U1 (MICOM, Z8601), LCD, key
matrix, LED indicators, SCAN position sensor and
the document detect sensor. Refer to OPE Schematic
Diagram and Wiring Diagram sections of this manu-
al.
• Signals from the key matrix are delivered to
U1X/Y input pin group (P1-x).
• U1 pin 4 (TX DATA) is the UART code sent to
MAIN PBA.
• Display from the controller is received at U1 pin 5
(RX DATA).
• LCD drive signals are sent from U1 P2-x pin group,
P3-4~P3-6 pins.
• Machine status LED drive signals are sent from U1
P0-x pin group.
• Document detect sensor output is received at U1
pin 33 (P3-3).
• Scan position sensor output is received at U1 pin 43
(P3-1).
RESONATOR
7.37 MHz
11
LCD
16 x 2 lines
7
X
Y 8
8
Key Matrix
LEDs
6-25