Icom IC-91A Service Manual page 17

5-6 CPU PORT ALLOCATION (continued)
Pin Port
No. Name
44 DTMF Outputs DTMF/beep/1750 Hz tone signals.
Input port for tone signals (B_BAND; CTCSS,
45 BTONE DTCS, etc.) from the tone selector (MAIN UNIT;
IC703).
Input port for tone signals (A_BAND; CTCSS,
46 ATONE DTCS, etc.) from the tone selector (MAIN UNIT;
IC703).
Input por t for RSSI signal from the D/A
47 S-LV
converter (MAIN UNIT; IC700).
Input port for audio level setting signal from the
48 VOL
volume controller (MAIN UNIT; S702).
Input port for RSSI signal (B_BAND) from the IF
49 BRSSI
IC (MAIN UNIT; IC200).
Input por t for transceiver's temperature
50 TEMP detection signal from the detecting temperature
selector (IC50).
Input por t for the volatge level from the
51 VIN
connected power supply.
Input port for reset signal from the reset IC
59 RESET
(IC100).
Outputs CPU clock frequency shift signal to the
69 CLSFT
clock frequency oscillator (X1, D103).
Outputs ACQ signal to the modem IC (UT-121;
†
70 ACQ
IC202).
Outputs DSEL signal to the modem IC (UT-121;
†
71 DCEL
IC202).
Input port for RX clock signal from the modem
†
72 RXCK
IC (UT-121; IC202).
Input port for RX data to the modem IC (UT-121;
†
73 RXDT
IC202).
Outputs TX data to the modem IC (UT-121;
†
74 TXDT
IC202).
Input port for TX clock signal from the modem
†
75 TXCK
(UT-121; IC202).
Outputs data signal to the RS-232C driver
83 TX232
(IC52).
Input port for data signal from the RS-232C
84 RX232
driver (IC52).
Outputs AME clock signal to the DSP IC
†
85 AMBECLK
(UT-121; IC101).
Outputs AME reset signal to the DSP IC (UT-121;
†
86 AMBERES
IC101).
Outputs strobe signal to the D/A converter
87 IOSTB3
(MAIN UNIT; IC701).
Outputs AME strobe signal to the DSP IC
†
88 AMBESTB
(UT-121; IC101).
Input port for AMEEPR signal from the DSP IC
†
89 AMBEEPR
(UT-121; IC101).
Outputs +3D line control signal to the 3.3 V
90 DVC regulator (UT-121; Q50, Q51).
"Low"=During DV
Outputs mode select signal to the mode switch
91 D_AS (IC301).
"Low"=During DV
Outputs power control signal to the B_BAND
92 BPS PLL IC (MAIN UNIT; IC400).
"Low"=During in power save mode.
Input port for unlock signal from the PLL IC (RF
93 UNLK UNIT; IC800).
"Low"=While the PLL is unlocked.
Outputs data signal to the PLL IC's (MAIN UNIT;
94 PLLDATA
IC400, RF UNIT; IC800).
Outputs strobe signal to the PLL IC (MAIN
95 BPLSTB
UNIT; IC400).
†
Available for the IC-91AD or when UT-121 is installed into
the
IC-91A.
Description
†
mode operation.
†
mode operation.
5 - 10
Pin Port
No. Name
Outputs strobe signal to the D/A converter
96 IOSTB2
(MAIN UNIT; IC702).
Outputs AF power amplifi er control signal to the
97 AFON AF6V regulator (Q105, Q106).
"High"=While the squelch is open.
Outputs strobe signal to the A_BAND PLL IC
98 APLLSTB
(RF UNIT; IC800).
• Outputs transmitter circuit control signal to the
LED dr iver (Q200) and the T5 regulator
99 TXC
(MAINUNIT; Q650–Q652)
"High"=While transmitting.
Outputs microphone amplifi er (Q302) and ALC
circuit (IC301) control signal to the microphone
100 MICC
amplifi er driver (Q300).
"Low"=While transmitting.
Description