5-7. Ic Pin Function Description - Sony XR-1800R Service Manual

5-7. IC PIN FUNCTION DESCRIPTION

• MAIN BOARD IC1 MN1884820SF (SYSTEM CONTROLLER)
Pin No. Pin Name
1 TUNMUT
2 AMPON
3 ILLON
4 PW ON
5 AMPMUTE
6 NIL
7 VDD1
8 X IN
9 X OUT
10 GND
11 XT IN
12 XT OUT
13 EX2
14 RESET
15 RDSCKI
16 BU IN
17 KEYACK
18 VOLSO
19 VOLCKO
20 VOLCE
21 TAPE MUTE
22 to 24 NCO
25 AMS ON
26 ATA ON
27 TAPE IN
28 FF-REW IN
29 N/R
30 RDSSI
31 AD ON
32, 33 NCO
34 CM ON
35 TAPE ON
36 ACC IN
37 PLLSI
38 BEEP
39 PLLSO
40 PLLCLK
41 PLLCE
42 LCD INH
I/O
O FM audio signal muting control output terminal "H": muting on
O Standby control signal output to the power amplifier (IC500) "L": standby
Power supply on/off control signal output terminal at the illumination and liquid crystal display
O
driver (IC900) "H": power on
O Main system power supply on/off control signal output terminal "H": power on
O Muting control signal output to the power amplifier (IC500) "L": muting on
I Not used (fixed at "L")
— Power supply terminal (+5V)
I Main system clock input terminal (8 MHz)
O Main system clock output terminal (8 MHz)
— Ground terminal
I Sub system clock input terminal (32.768 kHz)
O Sub system clock output terminal (32.768 kHz)
I Connected to ground
System reset signal input from the reset signal generator (IC50) and reset switch (S2)
I
"L" is input for several 100 msec after power on, then it changes to "H"
I Serial data transfer clock signal input from the RDS decoder (IC150)
I Battery detect signal input terminal "H": battery on
Input of acknowledge signal for the key entry Acknowledge signal is input to accept function
I
and eject keys in the power off status On at input of "H"
O Serial data output to the electrical volume (IC450)
O Serial data transfer clock signal output to the electrical volume (IC450)
O Chip enable signal output to the electrical volume (IC450)
O Tape muting on/off control signal output terminal "H": tape muting on Not used (open)
O Not used (open)
Tape auto music sensor control signal output terminal
O
"L" is output to lower the gain for audio level at FF/REW Not used (open)
I Not used (fixed at "H")
I Tape in detection switch (S903) input terminal "L": tape in
I FF/REW detection switch (S902) input terminal "L": FF/REW mode
Tape direction switch (S901) input terminal
I
"L: reverse direction, "H": forward direction
I Serial data input from the RDS decoder (IC150)
O Power supply on/off control signal output for the A/D converter "L": power on
O Not used (open)
O Capstan/reel motor (M901) drive signal output terminal "H": motor on
Tape system power supply on/off control signal output terminal "H": tape on
O
Not used (open)
I Accessory detect signal input terminal "L": accessory on
I PLL serial data input from the FM/AM PLL (IC121)
O Beep sound signal output terminal
O PLL serial data output to the FM/AM PLL (IC121)
O PLL serial data transfer clock signal output to the FM/AM PLL (IC121)
O PLL serial chip enable output to the FM/AM PLL (IC121)
Blank indicate control signal output to the liquid crystal display driver (IC900)
O
"L": no display
Function
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