Specifications

AL-1551 ELECTRICAL SECTION 12-18
13.Operation section
A. Outline
The operation circuit is composed of the key matrix circuit and the display matrix circuit.
B. Key matrix circuit
The CPU in the MCU sends select signals SELIN1 - 3 to the selector in the operation circuit. The signals detects ON/OFF of the key and are sent to the
CPU as KIN1 - 2.
C. Display circuit section
The display is controlled by inputting the data signal and the clock signal from the CPU and the latch signal from the ASIC to the LED driver in the
operation circuit.
CPU
Selector
IC902,903
+5V
Key
Operation circuit
MCU
+5V+5V
Operation circuit
MCU
CPU
ASIC
Display
LED
LED driver
IC901
OP-CLK
OP-DATA
OP-LATCH