Port Allocations; Cpu - Icom IC-2800H Service Manual

4-5 PORT ALLOCATIONS

4-5-1 CPU (MAIN UNIT; IC19)
Pin Port
number name
Input port for the decoded CTCSS sig-
1 TONEIN
nals.
OSC1,
Input ports for the CPU system clock
7, 8
OSC2 oscillator (X4: 10.000 MHz).
9 RES
Input port for the reset signal.
11 CLONEC
I/O port for the cloning signal.
Outputs strobe signals for the PLL IC
12 PLSTB
(IC2).
Outputs strobe signals for the D/A con-
13 STB
vertor (IC3).
Outputs serial clock signal for the PLL
14 CK
IC (IC2) and D/A convertor (IC3).
Outputs serial data signals for the PLL
15 DATA
IC (IC2) and D/A convertor (IC3).
Input port for serial signal from the
16 RXD
sub-CPU (CONTROL unit; IC10)
Output port for serial signal to the sub-
17 TXD
CPU (CONTROL unit; IC10)
Outputs clock signal for the EEPROM
19 ESCK
IC (IC17).
Input port for serial signal from the
20 ESI
EEPROM IC (IC17).
Outputs data signal for the EEPROM
21 ESO
IC (IC17).
Outputs chip select signal for the EEP-
22 ECS
ROM IC (IC17).
Input port for microphone serial signal
23 MICIN
via the MDATA controller (IC24).
Input port to detect remote microphon
24 EXTMIC connection.
Low : HM-90/98 is connected.
25 ETONE Outputs 1750 Hz Europe tone signal.
Outputs power switching circuit (Q74,
26 PCTRL Q75) control signal.
High : While turning power ON.
Outputs serial clock signal for the elec-
34 VCK
tronic volume IC (IC10).
Outputs data signal for the electronic
35 VDATA
volume IC (IC10).
Input port for packet PTT signal.
44 PTTP1
High : Packet PTT switch is ON.
Input port for the PTT switch.
45 PTTM1
High : While PTT switch is pushed.
PLL unlock signal input port for VHF
46 VUNLK
band.
High : PLL unlock on VHF band.
PLL unlock signal input port for UHF
47 UUNLK band.
High : PLL unlock on UHF band.
Outputs control signal for the V-BIAS
52 1RX
selector (Q34, Q35).
High : While receiving on VHF band.
Output control signal for the U-BIAS
54 4RX
selector (Q34, Q36).
High : While receiving on UHF band.
Outputs Rx/Tx pass-bandwidth control
signal.
59 W/N
High : While narrow bandwidth is
Description
selected. ([EUR], [ITA] only)
Pin Port
number name
60 VTX
61 UTX
64 MMUTE
POWC0–
68–75
POWC7
78 FUNK
79 UAMUTE
80 VAMUTE
81 UDMUTE
82 VDMUTE
83 OPD
85–85 Q1–Q4
90 CTCSS
91 DTMF
4-5-2 SUB-CPU (CONTROL UNIT; IC10)
Pin Port
number name
5 LRES
10 TXD
11 RXD
VSQLV,
59, 60
VVOLV
USQLV,
61, 62
UVOLV
VDLA,
73, 74
VDLB
VDLA,
75, 76
VDLB
77 BRITV
79 CONTV
4 - 6
Description
Outputs transmit signal for VHF band.
High : While transmitting on VHF
band.
Outputs transmit signal for UHF band.
High : While transmitting on UHF
band.
Outputs MIC mute control signal.
Low : While DTMF signals are out-
put, etc.
Output ports for output power control
signal.
Outputs cooling fan control signal.
High : While transmitting or after
transmission for 2 minute.
Outputs mute control signal for UHF
AF signals.
High : While UHF squelch is activate.
Outputs mute control signal for VHF
AF signals.
High : While VHF squelch is activate.
Outputs mute control signal for UHF
demodulated signals.
High : While UHF demodulated sig-
nals are muted.
Outputs mute control signal for VHF
demodulated signals.
High : While VHF demodulated sig-
nals are muted.
Input port for detection signal from the
DTMF unit.
Low : While DTMF unit is connected.
Input ports for the decoded DTMF sig-
nal from the DTMF unit.
Outputs CTCSS signals.
Outputs DTMF signals.
Description
Outputs reset signal for the LCD con-
troller (IC8).
Input port for serial signal from the
main-CPU (MAIN unit; IC19)
Output port for serial signal to the
main-CPU (MAIN unit; IC19)
Squelch/volume setting level input
ports for VHF band.
Squelch/volume setting level input
ports for UHF band.
Input ports for the up/down signals
from the VHF main dial.
Input ports for the up/down signals
from the VHF main dial.
Outputs brightness control signal for
the display backlight.
Outputs control signal for the contrast
of display.