Icom IC-M400BB, Service Manual

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4-5
4-5 PORT ALLOCATIONS
• CPU (LOGIC UNIT: IC1)
• D/A CONVERTER (MAIN UNIT: IC514)
PIN
No.
LINE
NAME
DESCRIPTION I/O
26 TEMPV Temperature sensing voltage. I
27 TDETV Transmit output power sensing voltage. I
28 LOINV Lock voltage input. I
29 WDECV Weather alert signal detect. I
40 DSCOUT DSC signal encoding output. O
41 BEEP Beep audio. (Square waves) O
44 NOISEV Noise level detect. I
46 LBAT Power supply voltage. I
58 SDATA Common serial data. I
59 SCK Common serial clock. I
63 DASTB
D/A converter (MAIN UNIT: IC514)
strobe.
I
64 PLSTB PLL (MAIN UNIT: IC101) strobe. I
65 IOSTB
Expander (MAIN UNIT: IC801 and
IC802) strobe.
I
69 COM1TXD
Serial data to the COMMANDMI-
C
IV
™.
O
70 COM1RXD
Serial data from the COMMANDMI-
C
IV
™.
I
77 REXTM
RX AF mute switch (MAIN UNIT:
IC504) control. (For COMMANDMI-
C
IV
™)
L=AF mute.
O
78 RXSPM
RX AF mute switch (MAIN UNIT:
IC504) control. (For public address)
L=AF mute.
O
101 NM1TXD NMEA output. O
102 NM1RXD NMEA input. I
103 DSCIN Decoded DSC signal input. I
113 CLOTXD Cloning data. O
114 DTEST DSC loop back testing signal. O
116 CLORXD Cloning data. I
117 PON
Power supply line VCC control.
L=While the transceiver's power is ON.
O
135 UNLKI
PLL unlock detect.
L=Unlocked.
I
136 DIMM LCD brightness control. O
141 ECK
EEPROM (LOGIC UNIT: IC9) serial
clock.
O
142 EDATA
EEPROM (LOGIC UNIT: IC9) serial
data.
I/O
PIN
No.
LINE
NAME
DESCRIPTION
2 AFVOLO AF output level adjustment. (RX signal)
3 FCON Reference frequency adjustment.
11 SQL Noise squelch level adjustment.
14 MSENS MIC sensitivity adjustment.
15 PCON TX output power adjustment.
23 PAVOLO
AF output level adjustment. (Public ad-
dress signal)