Kirisun PT4200 Service Manual page 7

DCS
DCS (digital code squelch) is a kind of continuous digital code
modulated with voice signals on carrier wave to control squelch.
83 groups of standard codes (positive and inverse code) are
available. See table 3.2.
DCS signals generated by MCU (PWM wave shape) pass the
low pass filter to be filtered off the high frequency over 300Hz and
then are sent to VCO and TCXO for modulation. VCO modulates
the high frequency of DCS signals; TCXO modulates the low
frequency of DCS signals.
CTCSS/DCS signals from the receiver are sent to MCU for
modulation. MCU determines whether the DCS encoding of the
receiving signals is identical with that set on the radio and decides
whether to turn on the speaker.
Table 3.2 DCS Encoding List
023 114 174 315
025 115 205 331
026 116 223 343
031 125 226 346
032 131 243 351
043 132 244 364
047 134 245 365
051 143 251 371
054 152 261 411
065 155 263 412
071 156 265 413
072 162 271 423
073 165 306 431
074 172 311 432
3.7 Semiconductor Component
MCU Description
Table 3.3 Microprocessor (M38034) Port Description
Pin Port Pin I/O
No .
Name Name
1 TI P1 I
2 BUSY P2 I
3 BATT P3 I
4 ALARM P4 I
5 TO P5 O
6 BEEP P6 O
7 PF1 P7 I
8 ENC0 P8 I
9 P9 I
ENC2
10 ENC3 P10 I
11 ENC1 P11 I
12 P12 I
NC
13 PTT P13 I
14 TXD P14 O
15 P15 I
RXD
16 MONI P16 I
17 SELF P17 I
18 CNVSS P18 I
19 RST P19 I
20 INT0 P20 I
5
445 631
464 632
465 654
466 662
503 664
506 703
516 712
532 723
546 731
565 732
606 734
612 743
624 754
627
Function
QT/DQT signal input
Busy s ignal in put
Ba ttery vo ltage check
Alarm key check
QT/DQT output
Beep output/warning tone output
Voice indication key check
Encoding input
Encoding input
Encoding input
Encoding input
Not used
[PTT] key input, connected with RXD
RS-232C input
RS-232C input
[MONI] key input
Self programming
L: Model setting mode
Connect 10K resistor with VSS
R e set i nput
P o w er ch eck in put
PT4200
21 ENC P21 I
-SEL
22 XIN P22 I
23 XOUT P23 O
24 VSS P24 I
25 SHIFT P25 O
26 PABC P26 O
27 OSCSI P27 I
28 WNTC P28 O
29 PS P29 O
30 SDA P30 I/O
31 SCL P31 O
32 UL P32 I
33 DT P33 O
34 CK P34 O
35 LE P35 O
36 5MC P36 O
37 AFCO P37 O
38 RX P38 O
39 GLED P39 O
40 RLED P40 O
41 SAVE P41 O
42 MUTE P42 O
43 5RC P43 O
44 5TC P44 O
45 W588C P45 O
46 AC P46 O
47 DAOUT1 P47 O
48 DAOUT0 P48 O
49 DAOUT7 P49 O
50 DAOUT6 P50 O
51 DAOUT5 P51 O
52 DAOUT4 P52 O
53 DAOUT3 P53 O
54 DAOUT2 P54 O
55 NC P55 O
56 APC P 5 6 O
57 VCC P57 I
58 VREF P58 I
59 AVSS P59 I
60 IF_SEL I
P60
SERVICE MANUAL
Encoding switch selection.
Connect the pull down resistor with
VSS .
7.3MHz Osc illator
Earthing
Clock frequency shift H Open
Final power supply H Open
VCO crystal selection.
Connect the pull down resistor with
VSS H 13 L 16.8
Wide/Narrow band contro l
H Wide L Narrow
PLL p ower s aving co ntrol H No rmal
working L Power saving
EE PROM data wire
EE PROM cloc k wire
PLL unlock che c k pin H Locked
L Loss of lock
PL L data output
PL L clock output
PLL IC en abl i n g pin H L atched
Power control excep t CPU and
EEPROM L Open
Audio amplification power H:Open
TX/RX VCO Se l e c tion H Rece iving
Gree n indicato r contro l H Ligh t
Re d indicato r contro l H Light
Battery power saving c o ntrol
H Power supply L Power saving
Squelc h contro l
H L Audio squelch
Mic squelch
eceiving power control L Open
R
Transmitter power control H Open
Voice indication H Voice
annunciation of channel
Alert control H Control by voice
volume. It must be in low battery level
when in emergency alert state .
D/A output 1
D/A output 0
D/A output 7 frequency regulated
output VCCN
D/A output6
D/A output5
D/A output4
D/A output3
D/A output2
Not used
TX Auto power contro l outpu t
RX BPF tuning output
CPU pow er 5V input
Connected with VCC
Conn ecte d with VSS
IF selection. Connect the pull down
resistor with VSS H 49.95 L 21.4