Philips ACT-500 Service Manual page 17

PIN DESCRIPTIONS OF IC
MCU MN101C39C_399
Name No. I/O
SEG1 79 Output
SEG0 80
MMOD 14 Input
NWE 50 Output
NRE 51 Output
NCS 52 Output
NDK 31 Input
A0 55 Output
56 Output
A1
A2 57 Output
A3 58 Output
A4 59 Output
A5 60 Output
A6 61 Output
A7 62 Output
A8 63 Output
A9 64 Output
A10 65 Output
A11 66 Output
A12 67 Output
A13 68 Output
A14 69 Output
A15 70 Output
A16 53 Output
A17 54 Output
D0 78 I/O
D1 77 I/O
D2 76 I/O
D3 75 I/O
D4 74 I/O
D5 73 I/O
D6 72 I/O
D7 71 I/O
Other
Function
LCD segment output
Memory mode switch
input pin
P50, LED0 Write enable pin
(Active low)
P51, LED1 Read enable pin,
LED0
P52, LED2 (Active low)
Chip select pin
P06, BUZZER (Active low)
Data acknowledge pin
P60, SEG25 (Active low)
P61, SEG24 Address pin
P62, SEG23
P63, SEG22
P64, SEG21
P65, SEG20
P66, SEG19
P67, SEG18
P70, SDO0, SEG17
P71, SDO1, SEG16
P72, SDO2, SEG15
P73, SDO3, SEG14
P74, SDO4, SEG13
P75, SDO5, SEG12
P76, SDO6, SEG11
P77, SDO7, SEG10
P53, SEG27, LED3
P54, SEG26, LED4
P80, SEG2
P81, SEG3 Data pin
P82, SEG4
P83, SEG5
P84, SEG6
P85, SEG7
P86, SEG8
P87, SEG9
3 - 7
Function
Connect to segment pins on the LCD panel.
This pin sets the memory expansion mode. Set this pin
always to low.
Memory control signals for an expanded memory
space outside this LSI.
NWE is a strobe signal output for writing to external
memory.
NRE is a strobe signal output for reading from external
memory.
NCS is a chip select signal output when external
memory is accessed.
NDK is an acknowledge signal that indicates the
external memory access is complete.
A0 to A17 are address signals output to external
memory.
Description