Yamaha A-S2100, Service Manual, Page: 48 / 115

• Microprocessor extended port
IC402: LC709004AMJ-AH (FRONT (1) P.C.B.)
I/O-expander for microprocessor
C
ontr
ol logic
port 0 I/O buffer
Serial/parallel converter/shift register
I/O control/output register
DIN
VDD
DOUT
VSS
CLK#
CS#
RES#
P00 P07
2
1
5
7
3
4
6
24 17
VDDP1
16
port 1 I/O buffer
P1
0
P1
7
15 8
Pin
No.
Port Name
Function Name
(P.C.B.)
I/O
Detail of Function
P
o
w
er On [All]
Standb
y
MCU Sleep [When wr
iting]
2 DIN DIN SI Data In
3 CLK# CLK SI Clock
4 CS# CS I Chip Select
5 VDD VDD Power source
6 RES# RES I Initial Clear
7 VSS VSS GND
8 P17 NC
9 P16 MTR MT O Hi/HiZ: OFF, Low: ON (Mute)
10 P15 COLOR I O O Main unit color / Hi: BL, Low: SI
11 P14 MTR_ATT O Hi/HiZ: OFF / Hi: HP inserted (OFF), Low: when no HP (ON: ATT)
12 P13 PK/N_VU O Hi: Peak mode, Low: VU mode
13 P12 MTR_OFF O HiZ HiZ Hi/Hiz: Meter Off
14 P11 RY_HP O ON when the headphone is detected
15 P10 LED_MT HiZ LEDs are made to turn on when the MUTE lever on the front
and the MUTE key of the remote control unit are operated
16 VDDP1 VDDP1 +5S power
17 P07 LED_MDIR HiZ LED is turned On when INPUT MAIN DIRECT is selected
18 P06 LED_PHONO HiZ LED is turned On when INPUT PHONO is selected
19 P05 HiZ
20 P04 LED_BAL1 HiZ LED is turned On when INPUT BAL is selected
21 P03 LED_LINE2 HiZ LED is turned On when INPUT LINE2 is selected
22 P02 LED_LINE1 HiZ LED is turned On when INPUT LINE1 is selected
23 P01 LED_TU HiZ LED is turned On when INPUT TUNER is selected
24 P00 LED_CD HiZ LED is turned On when INPUT CD is selected
48
A-S2100
A
-S21
0
0