Icom IC-7800 Service Manual Addendum page 360

3-7-2 FRONT CPU (DISPLAY BOARD; IC6)
Pin Port
number name
1 CNTV Outputs LCD contrast control signal.
Outputs LCD brightness control sig-
2 BRIV
nal.
Outputs data signal to the SERI PARA
3 LDAT
IC (IC7, pin 3).
Outputs strobe signal to the SERI
4 LST
PARA IC (IC7, pin 5).
Outputs clock signal to the clock IC
5 RTCCK
(IC601, pin 6).
Outputs the clock IC (IC601, pin 3)
select signal.
8 RTCCE
High : The clock IC is selected.
Outputs [MONITOR] LED control sig-
9 MOND
nal.
Input port for B phase signal from
17 RSB
[RIT] control (150 pulse).
Input port for A phase signal from
18 RSA
[RIT] control (150 pulse).
Input port for B phase signal from sub
19 SSB
dial (1000 pulse).
Input port for A phase signal from sub
20 SSA
dial (1000 pulse).
Input port for B phase signal from
21 MSB
main dial (1000 pulse).
Input port for A phase signal from
22 MSA
main dial (1000 pulse).
Outputs [TIMER] LED control signal.
23 TMD
High : While lighting.
Outputs LED brightness control sig-
24 LEDV
nal.
Outputs LCD backlight control signal.
25 BKLS
High : While lighting.
26 CFLV Outputs CFL backlight control signal.
Input port for the detecting signal
whether the headphones are connect-
28 PHNI
ed or not.
High : Headphones are connected.
33 LTXD Outputs data signals by 38400 bps.
34 LRXD Input port for data signals by 38400 bps.
Input port for the connected electric
35 DOTK
keyer DOT signal.
Input port for the connected electric
36 DSHK
keyer DASH signal.
37 SQSS Outputs squelch signal to [MIC] jack.
I/O port for data signals from/to the
38 RTCDT
clock IC (IC601, pins 4 or 5).
Input port for [SPEECH] for the main
39 MSPK
band.
40 TRAK Input port for [TRANSMIT].
41 F1K Input port for [F-1].
42 F2K Input port for [F-2].
43 F3K Input port for [F-3].
45 F4K Input port for [F-4].
Description
Pin Port
number name
46 F5K
47 F6K
48 F7K
49 SSBK
50 CWK
51 RTYK
52 AMK
53 DATA
54 MSCK
55 EXTK
56 PLYK
57 RECK
58 XFCK
59 EQRK
61 MINK
63 CHGK
64 SUBK
65 MPRK
66 MWK
67 UPK
68 DWK
69 MPWK
70 VMK
71 MATK
72 MTSK
73 PWRK
74 MLCK
75 SATK
76 STSK
77 SSPK
78 SLCK
79 SP2B
80 SP2A
81 SP1B
82 SP1A
83 MP2B
84 MP2A
85 MP1B
86 MP1A
3 - 16
Description
Input port for [F-5].
Input port for [F-6].
Input port for [F-7].
Input port for [SSB.
Input port for [CW].
Input port for [RTTY/PSK].
Input port for [AM/FM].
Input port for [DATA].
Input port for [M.SCOPE].
Input port for [EXIT/SET].
Input port for [PLAY].
Input port for [REC].
Input port for [XFC].
Input port for [M=S].
Input port for [MAIN].
Input port for [CHANGE].
Input port for [SUB].
Input port for [MP-R].
Input port for [MW].
Input port for [∫].
Input port for [√].
Input port for [MP-W].
Input port for [V/M].
Input port for [AUTO TUNE] for main
band.
Input port for [TS] for main band.
Input port for [POWER].
Input port for [LOCK] for main band.
Input port for [AUTO TUNE] for sub
band.
Input port for [TS] for sub band.
Input port for [SPEECH] for sub band.
Input port for [LOCK] for sub band.
Input port for B phase signal from
[PBT2] dial for sub band.
Input port for A phase signal from
[PBT2] dial for sub band.
Input port for B phase signal from
[PBT1] dial for sub band.
Input port for A phase signal from
[PBT1] dial for sub band.
Input port for B phase signal from
[PBT2] dial for main band.
Input port for A phase signal from
[PBT2] dial for main band.
Input port for B phase signal from
[PBT1] dial for main band.
Input port for A phase signal from
[MAIN PBT1] dial.