HYT TC-320 User manual

８１３００３２００００１０

Contents
Revision History ---------------------------------------------------------------------------------------------------------1
Copyright Information -------------------------------------------------------------------------------------------1
Disclaimer------------------------------------------------------------------------------------------------------------------------1
Introduction-----------------------------------------------------------------------------------------------------------------------2
Radio Overview-----------------------------------------------------------------------------------------------------------------3
Software Specifications------------------------------------------------------------------------------------------------------4
Circuit Description------------------------------------------------------------------------------------------------------9
CPU Pins-------------------------------------------------------------------------------------------------------16
Parts List 1---------------------------------------------------------------------------------------------------------20
Adjustment Description --------------------------------------------------------------------------------33
Troubleshooting Flow Chart--------------------------------------------------------------------------------------------43
Disassembly and Assembly-----------------------------------------------------------------------------------------------46
Exploded View------------------------------------------------------------------------------------------------------49
Parts List 2--------------------------------------------------------------------------------------------------------53
Packing Diagram--------------------------------------------------------------------------------------------------------55
PCB View-------------------------------------------------------------------------------------------------------56
Level Diagram------------------------------------------------------------------------------------------------------58
Block Diagram------------------------------------------------------------------------------------------------------59
Schematic Diagram--------------------------------------------------------------------------------------------------------60
Specifications-----------------------------------------------------------------------------------------------------------------66

TC-320 Service Manual
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Revision History
Part No. Date of
Issue
Description
8130032000000 2009.4 Initial Release
8130032000010 2010.9 Circuit Description, Schematic Diagrams, PCB View, Level
Diagram, Block Diagram, Parts List 1 & 2, and Specifications are
updated.
Copyright Information
Hytera and HYT are trademarks or registered trademarks of Hytera Communications Co., Ltd. (“Hytera”)
in PRC and/or other countries or areas. Hytera retains the ownership of its trademarks and product
names. All other trademarks and/or product names that may be used in this manual are properties of
their respective owners.
The Hytera product described in this manual may include Hytera computer programs stored in memory
or other media. Laws in PRC and/or other countries or areas protect the exclusive rights of Hytera with
respect to its computer programs. The purchase of this product shall not be deemed to grant, either
directly or by implication, any rights to the purchaser regarding Hytera computer programs. Any Hytera
computer programs may not be copied, modified, distributed, decompiled, or reverse-engineered in any
manner without the prior written consent of Hytera.
Disclaimer
Hytera endeavors to achieve the accuracy and completeness of this manual, but no warranty of
accuracy or reliability is given. All the specifications and designs are subject to change without notice
due to continuous technology development. No part of this manual may be copied, modified, translated,
or distributed in any manner without the express written permission of Hytera.
If you have any suggestions or would like to learn more details, please visit our website at:
http://www.hytera.cn.

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Introduction
Manual Scope
This manual is intended for use by qualified technicians only.

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Radio Overview
(1)PTT (Push-to-Talk)
Key (2)SK (Side Key ) (3) Speaker (4)Volume Adjust Keys [+]/[-]
(5) Microphone (6) Nameplate (7) Charging Terminal (8) Antenna
(9)Power Switch (10) Channel/Status
Indicator
(11)Channel Selector
Knob
(12)Charge
Indicator
(13)Accessory Jack
Cover (14)Accessory Jack (15)Mini USB Jack (16)Strap Hole
(17)Screw (Belt Clip) (18)Belt Clip (19)Rear Cover (20)Battery Latch

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Software Specifications
Status Indications
Operations/Functions LED Indications and Alert Tones
Power on the source radio while holding down SK,
and the LED flashes red once.
To enter Wired Clone mode
Turn on the target radio directly.
Status of the source radio
(After the target radio is turned
on and the cloning cable is
connected, hold down PTT of
the source radio to begin
cloning.)
The LED glows red during cloning process.
Error occurs during cloning:
a. User Clone: Once clone begins, frequency band
and radio ID (Model ID) will be checked. The LED
glows orange for 2 seconds and then goes out to
indicate a failed check. If the check is successfully
carried out but error occurs during data cloning, the
LED will flash orange. In this situation, press any key
other than the Power Switch to turn it off.
b. Factory Clone: If error occurs during data cloning,
the LED will flash orange until you press any key
other than the Power Switch to cancel it.
Once cloning is completed, the LED will glow green.
And if the battery runs low in Clone mode, the LED
will flash red.
Wired Clone
Mode
Status of the target radio The LED glows green when cloning is in progress.
The green LED goes out once cloning is completed.
Power On (to enter User Mode)
When the radio is turned on, an alert tone sounds and
the LED flashes orange once.
When the radio is currently on a blank channel, it
sounds beep tones continuously.
Power Off When the radio is turned off, the power-off alert tone
is heard.

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Low Battery Alert The LED flashes red, and a low-pitched tone sounds
every 10 seconds.
Transmitting
The LED glows red during transmitting.
When the TOT timer expires, the radio sounds beep
tones continuously.
A TOT pre-alert tone sounds before the TOT timer
expires.
Receiving The LED glows green during receiving.
Scan
The LED flashes green once every second during the
scanning process.
Scan Start Alert (programmable by the dealer): one
beep.
Scan End Alert (programmable by the dealer): one
beep.
Writing/Reading The LED glows red in reading data.
The LED glows green in writing data.
Power Adjustment
A low-pitched tone is heard when the radio switches
from high power to low power.
A high-pitched tone is heard when the radio switches
from low power to high power.
Monitor/VOX The alert tone sounds once if the feature is enabled.
The alert tone sounds twice if the feature is disabled.
Description of Modes
User Mode
It is a conventional communication mode. The radio will enter this mode if you turn it on directly.
PC Programming Mode
The radio in User Mode enters PC Programming Mode through specific protocol based communication
with the programming software. In this mode, radio functions and adjustment parameters can be set

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through the programming software (including User Version and Factory Version).
The operation procedures are as follows:
1) Install PC programming software and its driver dedicated for TC-320 before your initial use.
2) Connect the USB port of PC with the Mini USB jack of the radio using a programming cable.
3) Turn on the radio.
4) Launch the programming software to perform reading or writing operation.
Note:
1) When reading/writing data is in progress, red/green LED glows; when reading/writing data is
completed, red/green LED goes out.
2) During the operation, if any abnormal situation occurs or no reply is given within a period, the
reading/writing operation will fail and an error message window will pop up.
Wired Clone Mode
1. Description
Wired Clone Mode is an independent mode. To access other modes, you must restart the radio.
Wired Clone Mode covers User Clone Mode and Factory Clone Mode.
1）User Clone Mode:
Connect two radios using a clone cable. Power on the source radio while holding down SK, and it
will enter User Clone Mode after 2 seconds. The target radio can be directly turned on to enter user
mode. In this mode, data stored in EEPROM of the source radio will be cloned to EEPROM of the
target radio. The data transferred only involves channel data and common parameters, excluding
adjustment data, version and serial No. of the model.
2）Factory Clone Mode:
Connect two radios using a clone cable. Power on the source radio while holding down SK, and it
will enter User Clone Mode by default after 2 seconds. Press SK afterwards to switch to Factory
Clone Mode. The target radio can be directly turned on to enter the mode. The data transferred
covers all data in EEPROM other than serial No, with flag of manual adjustment switch included.
2. Process
Process of Wired Clone:
1) The LED flashes red once after the source radio enters Wired Clone Mode. Hold down PTT to clone
data to the target radio.

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2) During communication, LED of the source radio glows red, and LED of the target radio glows green.
When communication finishes, LED of the source radio glows green and LED of the target radio goes
out, indicating that both radios are ready for another cloning operation.
3) If any abnormal situation occurs during cloning, the source radio will stop cloning and its LED will flash
orange, indicating both radios are ready for another cloning operation.
4) When the communication ends, the source radio goes back to standby status. Hold down PTT again
to begin another cloning.
Manual Adjust Mode
Hold down PTT and SK on the radio while powering it on, and the radio enters Manual Adjust Mode.
(Note: This operation is subject to the option Panel Test Mode in the programming software. When this
option is unchecked, the radio will be unable to enter the adjustment mode. It helps avoid change of
parameters and degradation of radio performance caused by user’s misoperations. )
Keep this option unchecked after values are well adjusted from factory, to avoid any unexpected change
of values. The adjustment values can be reset and changed in Factory Mode only.
Description of adjustment:
1) To enter Manual Adjust Mode
Hold down PTT and SK for 2 seconds while powering on the radio. The LED will glow orange when the
radio is in Adjust Mode. When the keys are released, the radio will enter item N of TX group (N depends
on the position where the Channel Selector knob locates).
2) To switch between TX group and RX group
This operation is done through the Channel Selector knob.
The LED glows red when adjusting items in TX group.
The LED glows green when adjusting items in RX group.
3) To switch between items of TX group/RX group
This operation is done through the Channel Selector knob.
TX group: CH1 to CH9 stand for TX Low Power, TX High Power, CDCSS Balance, CDCSS Deviation,
CTCSS Deviation (low), CTCSS Deviation (medium), CTCSS Deviation (high), TX Low Voltage
Threshold and Max. Deviation of TX Audio respectively.
The LED solidly glows red when adjusting items CH1 to CH9.
RX group: CH10 to CH12 stand for SQL On 5, SQL Off 5, and RX Low Voltage Threshold respectively.

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The LED solidly glows green when adjusting items CH10 to CH12.
CH13 to CH16 are invalid and the LED goes out, indicating that no adjustment item is carried out.
4) To switch between wide and narrow bandwidth
In adjusting a certain item, short press SK (the LED flashes orange to indicate valid press) to switch
between wide and narrow bandwidth. After this operation, the first frequency of the current bandwidth is
the frequency for adjustment by default.
5) To switch frequency
Short press PTT (the LED flashes green to indicate valid press) to switch frequency one by one, under
certain bandwidth and adjustment item.
6) To increase/decrease adjustment value under certain bandwidth and adjustment item
Short press [+] under certain bandwidth and adjustment item, and the adjustment value will increase in
steps of 1; hold down [+], and the adjustment value will keep increasing in steps of 1. The adjustment
value will remain unchanged once it reaches the allowed maximum value.
Short press [-] under certain bandwidth and adjustment item, and the adjustment value will decrease in
steps of 1; hold down [-], and the adjustment value will keep decreasing in steps of 1. The adjustment
value will remain unchanged once it reaches the allowed minimum value.
7) Operations on special items:
TX group: CH8 is the TX Low Voltage Threshold. This adjustment item is related to AD sampling. Press
[+] or [-] after entering the above item, to activate AD sampling (including calculation) once. Rotate the
Channel Selector knob to save the current AD sampling value.
RX group: CH10 to CH12 stand for SQL On 5, SQL Off 5, and RX Low Voltage Threshold respectively.
These adjustment items are related to AD sampling. Press [+] or [-] after entering the above items, to
activate AD sampling (including calculation) once. Rotate the Channel Selector knob to save the
current AD sampling value.
8) Description of key press:
Short press: key press no longer than 1 second;
Long press: key press time longer than 1 second.

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Circuit Description
1. General Diagram
The general circuit is composed of TX section, RX section, power supply circuit, control circuit and etc.
The block diagram is shown in the figure below:
QT_MOD
SW
U605
D504
VOX
D505
C522
Q105
Q406
LO
Q104
Q611
LO
VR601
AT41511
Q503
R204
MOD
CHARG
BUSY
QT_OUT
R602
RF AMP
SAVE
AMP
Q103
D105
RESET
R603
Q505
U101
VCO_IN
MIX
CD501
MB15E03SL
VCC
CF 501
XF501
SW602
SW PB
1
2
D503
R632
B302
Speaker
+
1
-
2
D502
SW604
SW PB
1
2
VCO_IN
W401
ANTENNA
1
B201
MIC
+
1-
2
SW605
SW PB
1
2
UP
Q102
DOW
TX/RX SW
APC Q506
RFC
AF_OUT
QT_OUT
X6 0 1
Q502
Q501
R103
CKSTB/
TX_CTL
V1
C132
DATA/
V2
Q602
MOD_OUT
U601
D602
LED
1 2
D603
LED
1 2
SW606
R633
U301
U604
BUSY(SQL)
LD(SIG OUT)
BAT
RFC
G601
BATTERY
1 2
SWAF 501
SWAF 502
D604
12
LPFRF AMP
D102
APC
V_S AVE
12
RF AMP
D103
D101
PRE AMP
Q601
CP
VR
SWAF 503
MIC IN
XT1 0 1
SW603
SW PB
1
2
CHARG
CHARG
J202
AF(DEMOD)
1 212
SW
LOOP FILTER
R515
C553
IF AMP
J201
U603
NFIL IN
SW
SCL
SDA
VT
12
SW
TX OUT
U401
1 2
MON
PTT
SW
EC1
T_LED
R_LED
EC0
EC3
EC2
MON
DC-DC
PTT
SW601
SW PB
1
2
POWER
EEPROM
TXD
RXD
APA_EN
Q401
U602
Q402
VCO
AF
CP
Q403
C204
RIPPLE FILTER
MOD
D617
D616
NFIL OUT
MC3361P
U608
TX_OUT
21.25M OSCIN
QT_OUT
VC C
Q604
Q607
21.7M
Q608
VDD
D612
Q605
D401
D501
POWER
Figure 1
TX Section: The audio signal from MIC is sent to the MCU chip (U601) directly. The baseband signal
processing circuit in U601 converts the amplified audio signal to digital signal via A/D conversion, and
then converts the digital signal to modulation signal via D/A conversion after all processing procedures
such as filtering, signal compression, encryption, pre-emphasis, TX gain control and amplitude limiting
are completed. Then the modulation signal from MCU passes through the low-pass filter circuit and goes
to VCO for direct frequency modulation.
The modulated HF carrier signal passes through the buffer amplifiers (Q104 and Q406), and goes to the
amplifier (Q401) through the RF switching diode (D616). Then the amplified RF signal enters the
low-pass filter circuit through the switching diode (D401) after it is further amplified by the driver (Q402)
and final-stage power amplifier (Q403), and then it will be finally transmitted via antenna after high-order
harmonics are removed. The RX-TX switch circuit is composed of D401 and D501.

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RX Section: RF signal received via the antenna is fed to the bandpass filter (composed of SAWF501
and SAWF502) to filter out unwanted out-of-band interference signal, and then amplified by LNA Q503.
The amplified signal is then fed to the bandpass filter (SAWF503) to further filter out unwanted
out-of-band interference signal. The desired RF signal is mixed with the first local oscillator signal
(output from VCO) by Q505. The newly generated signal is processed by the crystal filter (XF501) to get
the first IF signal (21.7MHz). After amplified by Q506, this IF signal enters U608 to be further mixed with
the second LO (local oscillator) signal and to generate the second IF signal (450 KHz). This second IF
signal is demodulated by U608 to output audio signal, which is sent to MCU for A/D conversion and
filtering. Afterwards, the audio signal is divided into two flows. One flow is processed by CTCSS/CDCSS
decoder; the other is restored to audio signal through filtering, de-emphasis, decoding, signal expansion
and D/A conversion. Then the restored audio signal is amplified by the audio power amplifier (U301) to
drive the speaker directly.
Power Supply Section: The 3.8V battery voltage is converted to two flows of 3.0V DC voltage by the
LDO module (U602), that is, VCC and V_SAVE. VCC powers CPU while V_SAVE controls VT and VR.
VT goes through Q604 and Q601, and outputs 3V voltage for TX circuit under the control of TX-CTRL;
VR supplies 3V voltage for RX circuit under the control of Q604 and Q602. VDD (3V) supplies the PLL
U101 and XT101.
2. Realization Methods of Basic Functional Modules
2.1 PLL Frequency Synthesizer
The PLL circuit mainly provides the local oscillator signal for RX and RF carrier signal for TX. It is
composed of VCO and PLL processor, allowing frequency tracking and channel switching under the
control of MCU signals.
1）PLL

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Figure 2
The PLL circuit generates RF carrier signal for TX and the first local oscillator signal for RX.
PLL: Step frequency of the PLL circuit is 6.25 KHz, 10.0 KHz or 12.5 KHz. In U101, the 21.25MHz
reference oscillator signal is divided into 6.25 KHz, 10.0 KHz or 12.5 KHz reference frequencies via a
fixed counter in PLL. Processed by the buffer amplifier, the signal output from the VCO (TX/RX VCO)
enters PLL. The amplified signal is further processed in PLL by the variable frequency-divider. Then the
signal is compared with the reference frequency in the phase detector (PD) of PLL. The signal from the
PD passes through a low-pass filter, and then is sent to the varactors (D101 and D102) of VCO so as to
control output frequency. Then the RF signal is processed by the buffer amplifiers (Q104 and Q406),
and controlled by D616 and D617 to only serve as RF signal or RX first local oscillator signal.
2） VCO
VCO section is realized by the oscillator circuit of three-point capacitance. TX VCO and RX VCO share
the same oscillator circuit. In TX mode, Q103 is cut off and C130 gets invalid; in RX mode, Q103 is
turned on and C130 gets valid.
Note: If the PLL is unlocked, the LD pin of U101 outputs low level. If the microprocessor detects such
situation, TX/RX operation is prohibited, and an alarm sounds.
2.2 RF Power Amplifier Circuit (TX Section)
The block diagram of the RF power amplifier circuit is shown as below:

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W402
ANTENNA
1
V_BAT
R421
R420
R419
VT
Q405
LPFRF AMP
APC
RF AMPPRE AMP
APCSW SW
Q404
TX OUT
U401
Q401 Q402 Q403
Figure 3
The modulated carrier signal from VCO is pre-amplified by Q104 and Q406, and controlled at D617 and
D616. Then it is processed by the front-stage amplifier Q401, the pre-driver amplifier Q402 and the
final-stage amplifier Q403 respectively. Afterwards, the amplified RF signal enters the low-pass filter
(LPF) circuit through diode D401, and then is transmitted via the antenna after ultroharmonics are
removed.
APC circuit is composed of Q404, Q405 and U401. U401 controls the bias voltage at the gates of Q402
and Q403, to control TX current and to further regulate power.
2.3 RX LNA and Mixer Circuit (RX Section)
The block diagram of the RX circuit is shown as below:
Figure 4

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Desired and undesired RF signals received via the antenna are fed to the bandpass filter (composed of
SAWF501 and SAWF502) to filter out undesired out-of-band interference signal. Then the desired RF
signal is amplified by LNA Q503, and goes through the bandpass filter ( to filter out undesired
out-of-band interference signal. The desired RF signal is mixed with the first local oscillator signal
(output from VCO) by Q505. The newly generated signal is processed by the crystal filter (XF501) to get
the first IF signal (21.7MHz).
After amplified by Q506, this IF signal enters U608 to be further mixed with the second LO (local
oscillator) signal and to generate the second IF signal (450 KHz). Then the second IF signal is
demodulated by U608 to output audio signal, which is sent to MCU for A/D conversion and filtering.
Afterwards, the audio signal is divided into two flows. One flow is processed by CTCSS/CDCSS decoder;
the other is restored to audio signal through filtering, de-emphasis, decoding, signal expansion and D/A
conversion. Then the restored audio signal is amplified by the audio power amplifier (U301) to drive the
speaker directly.
2.4 MCU Control, Signal Processing and Audio Power Amplification
The block diagram of this section is shown as below:
R602
AMP
R603
SAVE
RESET
Q605
SW
1
2
ON/OFF
Q607
UPDOW
AF OUT
RFC
APC
QT_OUT
X6 0 1
TX_CTL
Q602
VOX
U601
D601
LED
1 2
D602
LED
1 2
SW606
VDD
U301
V_BAT
BUSY(SQL)
BAT
G601
BATTER Y
1 2
RESET
SP
VCC
V_SAVE
Q201
Q202
Q601
VT
U605
VR
POWER
TXD/RXD
Q604
J201
LD
U603
DATA
SDA
CK
SCL
STB
DEMOD
SW
T_LED
R_LEDEC0 EC1
SW
EC2 EC3
PTT
DC-DC
MON
EEPROM
U602
APA EN
MIC
MOD OUT
R/T
Figure 5

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2.4.1 MCU Control Circuit
MCU control circuit is composed of MCU, EEPROM, keys and etc. This section has the following
functions: to initialize data of the radio and save data to EEPROM; to detect battery voltage and signals
from external keys, LD and VOX, and to make response; to transmit required data to PLL based on the
channel encoding status; to switch and control RX/TX based on the input PTT signal; to switch the
squelch circuit on/off based on the input signaling decode signal and squelch level signal; to control
circuits of high/low power switch, audio power amplifier, VCO power supply, RX power supply and TX
power supply; (for programming) to communicate with PC via RXD/TXD based on the RS232 protocol,
and transmit/receive data to/from PC.
2.4.2 Signal Processing Section
a. TX Baseband Processing The audio signals input from MIC are divided into two flows. One flow
serves as the signal of VOX detection by Q508 and D612; the other enters U601, and then is converted
into digital signal by analog-to-digital conversion (ADC). Afterwards, the digital signal will go through a
series of processing including low-pass filtering, AGC, companding, high-pass filtering, encrypting and
pre-emphasizing. Finally, the signal is processed by the active low-pass filter and then sent to VCO for
modulation after it is converted by digital-to-analog conversion (DAC).
b. RX Baseband Processing
After entering U601, the DEMOD signal derived from IF demodulation is converted to digital signal via
analog-to-digital conversion (ADC), and then is sent to the digital low-pass filter. The signal is divided
into two flows. One flow is processed by CTCSS/CDCSS decoder; the other is processed by high-pass
filter, and then is subject to processing procedures such as de-emphasis, decryption, and signal
expansion, and finally is output as audio signal after digital-to-analog conversion.
2.4.3 Audio Power Amplifier
The audio signal output from U601 is amplified by the audio power amplifier (U301) to drive the speaker
directly.
2.5 Power Supply Processing
The block diagram of the power supply circuit is shown as below:

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Q605
SAVE
Q607
Q602
TX_CTL
VDD
G602
BATTERY
1 2
VCC
V_SAVE
Q601
VR
VT
Q604
POWER
DC-DC
SW
SW
U602
Figure 6
Power Supply Section: The 3.8V battery voltage is converted to two flows of 3.0V DC voltage by the
LDO module (U602), that is, VCC and V_SAVE. VCC powers CPU while V_SAVE controls VT and VR.
VT goes through Q604 and Q601, and outputs 3V voltage for TX circuit under the control of TX-CTRL;
VR supplies 3V voltage for RX circuit under the control of Q604 and Q602. VDD (3V) supplies the PLL
U101 and XT101.

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CPU Pins
Pin No. Port Name Pin Name I/O Function
1 NC / / /
2 NC / / /
3 NC / / /
4 NC / / /
5 NC / / /
6 TXD TXD O UART TXD
7 RXD RXD I UART RXD
8 P60 APA_EN O To control the speaker; H: unmute, L: mute
9 P61 SAVE_CTL O To control Power Save: it is at high level in
non-Power-Save status
10 P62 EXT MIC I To check MIC connection (valid at high level)
11 P63 EXT PTT I PTT key on the earpiece (valid at high level)
12 P64 Red LED O Red LED
13 P65 Green LED O Green LED
14 P66 Reserve O Reserved
15 P67 Reserve O Reserved
16 Vssd GND S Ground power supply for digital circuit
17 Vddd VCC (3.0V) S Power supply for digital circuit
18 P50/INT0 VOL+ I Volume Adjust Key [+]
19 P51/INT1 VOL- I Volume Adjust Key [-]
20 P52/INT2 Reserve O Reserved
21 P53/INT3 /POWER
SWITCH
I Power Switch
22 P54/INT4 SK I Programmable function key (side key) (valid at
low level), connected with a pull-up resistor
23 P55/INT5 PTT I PTT key (valid at low level), connected with a
pull-up resistor
24 P56/INT6 Reserve O Reserved
25 P57/INT7 Reserve O Reserved
26 Vdd_CLD VCC (3.0V) S Power supply for digital PA
27 CLD_OUTP AF_OUT O Audio output

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28 VSS_CLD GND S Ground power supply for digital PA
29 CLD_OUTM Reserve O Reserved
30 Vdd_CLD VCC (3.0V) S Power supply for digital PA
31 P77 RF_CTRL O To control RX frequency band; valid at high
level (high frequency band); valid at low level
(low frequency band)
32 P76/DAC1 APC DA To control TX power
33 P75/VREF VCC (3.0V) I Input pin of reference voltage of ADC and DAC
34 P74/DAC0 QT_OUT DA CTCSS/CDCSS output
35 P73/AD3 VOX AD VOX energy detection pin
36 Vssa GND S Ground power supply for analog circuit
37 Vdda VCC (3.0V) S Power supply for analog circuit
38 P72/AD2 Reserve AD Reserved
39 P71/AD1 SQL AD To detect noise
40 P70/AD0 BAT_DET AD To detect battery strength
41 XTAL0 OSC0 /
42 XTAL1 OSC1 / To connect 32.678KHz main crystal oscillator
43 PLL_CAP PLL_CAP / To connect the external capacitor (10nF) of PLL
44 NC / / /
45 NC / / /
46 NC / / /
47 NC / / /
48 NC / / /
49 P03/COM3 Reserve O Reserved
50 P02/COM2 Reserve O Reserved
51 P01/COM1 Reserve O Reserved
52 P00/COM0 Reserve O Reserved
53 P10/SEG0 Reserve O Reserved
54 P11/SEG1 Reserve O Reserved
55 P12/SEG2 Reserve O Reserved
56 P13/SEG3 Reserve O Reserved
57 P14/SEG4 Reserve O Reserved

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58 P15/SEG5 Reserve O Reserved
59 P16/SEG6 Reserve O Reserved
60 P17/SEG7 Reserve O Reserved
61 P20/SEG8 EN0 I
62 P21/SEG9 EN1 I
63 P22/SEG10 EN2 I
64 P23/SEG11 EN3 I
To detect input from the encoder switch
65 P24/SEG12 Reserve O Reserved
66 P25SEG13 Reserve O Reserved
67 P26/SEG14 Reserve O Reserved
68 P27/SEG15 Reserve O Reserved
69 P30/SEG16 Reserve O Reserved
70 P31/SEG17 Reserve O Reserved
71 NC / / /
72 NC / / /
73 NC / / /
74 NC / / /
75 NC / / /
76 P32/SEG18 Reserve O Reserved
77 P33/SEG19 Reserve O Reserved
78 P34/SEG20 Reserve O Reserved
79 P35/SEG21 Reserve O Reserved
80 P36/SEG22 Reserve O Reserved
81 P37/SEG23 POWER O Power control pin
82 P40/SEG24 Reserve O Reserved
83 P41/SEG25 SCL O EEPROM CLOCK, connected with a pull-up
resistor
84 P42/SEG26 SDA O EEPROM DATA, connected with a pull-up
resistor
85 P43/SEG27 LD I To detect PLL circuit unlock (H: lock; L: unlock),
connected with a pull-up resistor
86 P44/SEG28 DATA O PLL DATA
87 P45/SEG29 CK O PLL CLOCK