Sony WRR-855B, Service Manual, Page: 64 / 84

5-6
WRR-855B
Pin description of CPU
[Inputs]
Signal Name Pin No. Description
VDD 72 Power supply input ( + 5 Vdc)
Vpp 75 Power supply input ( + 5 Vdc) for PROM
Vss 33 GND for power supply
EXTAL 31 Clock input (8 MHz)
XTAL 32 Clock input
(8 MHz: Phase-reversal of EXTAL)
VLC3 35 Bias voltage for LCD
VLC2 36 Bias voltage for LCD
VLC1 37 Bias voltage for LCD
ALO 22 Audio signal level (analog)
RSSI(A) 23 RF signal level of ANTENNA A input
(analog)
RSSI(B) 24 RF signal level of ANTENNA B input
(analog)
TEMP 25 Temperature detection
BAT0 26 Power supply voltage (analog)
BAT2 27 Power supply voltage for tuner circuit
(analog)
DIST1 28 Not used
DIST2 29 Not used
TONE 13 Tone signal detection (L: detecting)
NOISE 14 Noise signal detection (L: detecting)
PLL-LD 16 PLL lock detection (H: Lock)
CH 1 Operation button (CH) (L: ON)
+
18 Operation button (
+
) (L: ON)
_ 19 Operation button ( _ ) (L: ON)
SQL SET 21 RSSI learning mode setting
(L: RSSI learning mode
when POWER is on)
MUTE 79 MUTING ON/OFF switch (L: ON)
GP 80 Operation button (GP) (L: ON)
RST 30 Reset
[Outputs]
Signal Name Pin No. Description
COM0, COM1 38, 39 LCD control
SEG0 to SEG19 42 to 61 LCD control
VL 34 Bias voltage control for LCD
SHDN 3 Control for shut down of IC761
(L: shut down)
WDT 4 Watch dog timer
RFG 11 Control for RF LED (green)
AFR 12 Control for AF LED (red)
RFR 20 Control for RF LED (red)
DIV 66 Diversity control
(H: ANT A, L: ANT B)
AFM 67 AF muting (H: Muting OFF)
[Inputs/Outputs for EEPROM and PLL]
Signal Name Pin No. Description
ROM-DO 17 EEPROM Control
ROM-CS 68 EEPROM Control
ROM-SK/PLL-CLK 69 EEPROM/PLL control
ROM-DI/PLL-DATA 70 EEPROM/PLL control
PLL-LE 77 PLL control
[Inputs/Outputs for communication]
Signal Name Pin No. Description
IF-CS 6 Serial I/O control
IF-CLK 7 Serial I/O control
IF-DI 8 Serial I/O control
IF-DO 9 Serial I/O control
[Others]
Signal Name Pin No. Description
PE4/RMC 2 NC
PB0/CS1 5 NC
PC2 15 NC
COM2, COM3 40, 41 NC
SEG20 to SEG23 62 to 65 NC
PF5/SEG29 71 NC
PF6/SEG30 76 NC
TX 73 NC
TEX 74 NC
PE0/INT0/EC 78 NC
PB5/SCK1 10 NC
CXP834P16Q-1-XXX
1
24
64
25
40
33 GND
80
65
72 VDD (+5 V)
Vpp (+5 V) 75
41
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