Icom ID-31A Service Manual page 15

• CPU (LOGIC UNIT: IC5) (Continued)
BALL LINE
No. NAME
N4 DSP_SI DSP (IC10) serial data.
DSP_
N5 DSP (IC10) "AFC" input.
AFC1
RTC_
N6 Serial data to the real time clock (IC4).
SDA
N7 PLLSTB PLL IC (MAIN UNIT: IC6) strobe.
N9 LCDDT LCD (DS10) serial data.
DSP_
N10 DSP (IC18) "DATA EMP" input.
DEMP
GPS module (CHASSIS: EP1) controller
N12 G_HIB (IC1) power control.
H: GPS module is ON.
N15 ECK EEPROM (IC7) clock.
P1 SD_CS MicroSD card chip select.
P2 SD_SCK MicroSD card clock output.
P4 DSP_CK DSP (IC18) clock.
DSP (IC18) operating mode control.
P5 DSP_PD
H: While in the power save mode.
P6 LCDRES LCD (DS10) reset.
P7 PLLDATA PLL IC (MAIN UNIT: IC6) serial data.
PLL lockup time control.
P9 PLL SW
L: Fast lockup time.
GPS module (CHASSIS: EP1) controller
P12 GPSC (IC1) switching.
H: GPS module's power is ON.
P13 RX232 RS-232C serial data input.
Internal PTT (MAIN UNIT: S2) input.
P14 INTPTT
L: Pushed.
R1 SD_RXD MicroSD card card data input.
R2 DSP_SO DSP (CI18) serial data.
DSP_
R4 DSP (IC18) "AFC" input.
AFC2
DSP_ DSP (IC18) reset.
R5
RESET H: Reset.
RTC_ Clock signal to the real time clock IC
R6
SCL (IC4).
R7 PLLCK PLL IC (MAIN UNIT: IC6) clock.
R8 LCDCK LCD (DS10) clock.
AF power AMP (MAIN UNIT: IC2) control.
R13 AFON
L: AF power AMP activated.
R14 EXTPTT External PTT input.
DESCRIPTION
• D/A CONVERTER (MAIN UNIT: IC11)
PIN LINE
I/O
No. NAME
I
7 BPF1
I
8 BPF3
I/O
11 SQLOUT
O
12 RXAFOUT RX AF output level adjustment.
O
19 VCOMOD
I
20 REFMOD
O
24 BPF2
O
O
O
O
O
O
O
O
O
I
I
I
O
I
O
O
O
O
O
I
4 - 5
DESCRIPTION
Tuning voltage to the BPF (D32, L40,
C353).
Tuning voltage to the BPF (D27, D29, D30,
L28, L31, L33, C286, C290, C292, C293,
C297, C299–C301, C304, C305).
Noise squelch level adjustment.
, D10–D12)
VCO (Q27 deviation adjust-
ment.
Reference oscillator (X1) deviation adjust-
ment.
Tuning voltage to the BPF (D27, D29, D30,
L28, L31, L33, C286, C290, C292, C293,
C297, C299–C301, C304, C305).
I/O
O
O
O
O
O
O
O