Nuvoton ARM Cortex-M User manual

NuMaker-NUC131U
May. 07, 2020 Page 1of 46 Rev 1.00
NUMAKER-NUC131U USER MANUAL
Maker Nu-mbed NUC472 User Manual
ARM®Cortex®-M
32-bit Microcontroller
NuMaker-NUC131U
User Manual
NuMicro®NUC131SD2AEU
The information described in this document is the exclusive intellectual property of
Nuvoton Technology Corporation and shall not be reproduced without permission from Nuvoton.
Nuvoton is providing this document only for reference purposes of NuMicro microcontroller based system
design. Nuvoton assumes no responsibility for errors or omissions.
All data and specifications are subject to change without notice.
For additional information or questions, please contact: Nuvoton Technology Corporation.
www.nuvoton.com

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Table of Contents
1Overview.............................................................................................7
2Features .............................................................................................8
3Hardware Configuration...........................................................................9
Front View............................................................................................... 93.1
Rear View..............................................................................................103.2
Extension Connectors................................................................................113.3
3.3.1 Pin Assignment for Extension Connectors................................................................ 11
3.3.2 Arduino UNO Compatible Extension Connectors ....................................................... 14
Power Supply Configuration ........................................................................163.4
3.4.1 VIN Power Source............................................................................................ 16
3.4.2 5 V Power Sources ........................................................................................... 16
3.4.3 3.3 V Power Sources......................................................................................... 17
3.4.4 1.8 V Power Sources......................................................................................... 17
3.4.5 Power Connectors............................................................................................ 17
3.4.6 USB Connectors .............................................................................................. 18
3.4.7 Power Switches............................................................................................... 18
3.4.8 Power Supply Models........................................................................................ 19
CAN Bus Interface....................................................................................223.5
External Reference Voltage Connector ...........................................................223.6
Ammeter Connector..................................................................................233.7
Push Buttons ..........................................................................................233.8
LEDs....................................................................................................233.9
Nu-Link2-Me...........................................................................................243.10
3.10.1 VCOM Switches............................................................................................... 24
3.10.2 Status LEDs ................................................................................................... 24
4Quick Start ........................................................................................ 25
Toolchains Supporting ...............................................................................254.1
Nuvoton Nu-Link Driver Installation................................................................254.2
BSP Firmware Download............................................................................274.3
Hardware Setup.......................................................................................274.4
Find the Example Project............................................................................294.5
Execute the Project under Toolchains.............................................................294.6
4.6.1 Keil MDK ....................................................................................................... 29

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4.6.2 IAR EWARM................................................................................................... 33
4.6.3 NuEclipse ...................................................................................................... 35
5NuMaker-NUC131U Schematics .............................................................. 41
Nu-Link2-Me...........................................................................................415.1
NUC131U platform ...................................................................................425.2
Extension Connector.................................................................................435.3
PCB Placement .......................................................................................445.4
6REVISION HISTORY............................................................................ 45

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List of Figures
Figure 1-1 NuMaker-NUC131U Development Board ...................................................................... 7
Figure 3-1 Front View of NuMaker-NUC131U................................................................................. 9
Figure 3-2 Rear View of NuMaker-NUC131U................................................................................ 10
Figure 3-3 NUC131SD2AEU Extension Connectors..................................................................... 11
Figure 3-4 Arduino UNO Compatible Extension Connectors......................................................... 14
Figure 3-5 External Power Supply Sources on Nu-Link2-Me ........................................................ 19
Figure 3-6 External Power Supply Sources on NUC131U platform .............................................. 20
Figure 3-7 Detach the Nu-Link2-Me from NuMaker-NUC131U..................................................... 21
Figure 3-8 Wiring between Ammeter Connector and Ammeter..................................................... 23
Figure 4-1 Nu-Link USB Driver Installation Setup.......................................................................... 25
Figure 4-2 Nu-Link USB Driver Installation.................................................................................... 26
Figure 4-3 Open VCOM Function .................................................................................................. 27
Figure 4-4 ICE USB Connector...................................................................................................... 27
Figure 4-5 Device Manger.............................................................................................................. 28
Figure 4-6 PuTTY Session Setting................................................................................................. 28
Figure 4-7 Template Project Folder Path....................................................................................... 29
Figure 4-8 Warning Message of “Device not found” ...................................................................... 29
Figure 4-9 Project File Migrate to Version 5 Format...................................................................... 30
Figure 4-10 Debugger Setting in Options Window......................................................................... 30
Figure 4-11 Programming Setting in Options Window................................................................... 31
Figure 4-12 Compile and Download the Project............................................................................ 31
Figure 4-13 Keil MDK Debug Mode............................................................................................... 32
Figure 4-14 Debug Message on Serial Port Terminal Windows.................................................... 32
Figure 4-15 IAR EWARM Window................................................................................................. 33
Figure 4-16 Compile and Download the Project............................................................................ 33
Figure 4-17 IAR EWARM Debug Mode ......................................................................................... 34
Figure 4-18 Debug Message on Serial Port Terminal Windows.................................................... 34
Figure 4-19 Import the Project in NuEclipse .................................................................................. 35
Figure 4-20 Import Projects Windows............................................................................................ 35
Figure 4-21 Open Project Properties Window ............................................................................... 36
Figure 4-22 Project Properties Settings......................................................................................... 36
Figure 4-23 Build Project................................................................................................................ 37
Figure 4-24 Open Debug Configuration......................................................................................... 37
Figure 4-25 Main Tab Configuration .............................................................................................. 38
Figure 4-26 Debugger Tab Configuration ...................................................................................... 38
Figure 4-27 Startup Tab Configuration .......................................................................................... 39

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Figure 4-28 NuEclipse Debug Mode.............................................................................................. 40
Figure 4-29 Debug Message on Serial Port Terminal Windows.................................................... 40
Figure 5-1 Nu-Link2-Me Circuit...................................................................................................... 41
Figure 5-2 NUC131U platform Circuit............................................................................................ 42
Figure 5-3 Extension Connectors Circuit ....................................................................................... 43
Figure 5-4 Front Placement ........................................................................................................... 44
Figure 5-5 Rear Placement............................................................................................................ 44

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List of Tables
Table 3-1 Extension Connectors.................................................................................................... 11
Table 3-2 NUC131SD2AEU Full-pin Extension Connectors and GPIO Function List................... 13
Table 3-3 Arduino UNO Extension Connectors and NUC131SD2AEU Mapping GPIO List......... 15
Table 3-4 Vin Power Source.......................................................................................................... 16
Table 3-5 5 V Power Sources........................................................................................................ 16
Table 3-6 3.3 V Power Sources..................................................................................................... 17
Table 3-7 1.8 V Power Sources..................................................................................................... 17
Table 3-8 Power Connectors ......................................................................................................... 17
Table 3-9 USB Connectors ............................................................................................................ 18
Table 3-10 Power Switches ........................................................................................................... 18
Table 3-11 Supply External Power through Nu-Link2-Me ............................................................. 19
Table 3-12 Supply External Power for NUC131U platform............................................................ 21
Table 3-13 CAN Bus Interface....................................................................................................... 22
Table 3-14 U10 Pin Connection..................................................................................................... 22
Table 3-15 External Reference Voltage Connector....................................................................... 22
Table 3-16 Ammeter Connector..................................................................................................... 23
Table 3-17 Push-Buttons ............................................................................................................... 23
Table 3-18 LEDs ............................................................................................................................ 23
Table 3-19 Nu-Link2-Me VCOM Switches..................................................................................... 24
Table 3-20 Operation Status LED Patterns ................................................................................... 24

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1 OVERVIEW
The NuMaker-NUC131U is a development board for Nuvoton NuMicro®NUC131SD2AEU
microcontrollers. The NuMaker-NUC131U consists of two parts: an NUC131U platform and an on-
board Nu-Link2-Me debugger and programmer. The NuMaker-NUC131U is designed for project
evaluation, prototype development and validation with power consumption monitoring function. The
NuMaker-NUC131U is suitable for automotive and industrial control applications developing which
need reliable and robust CAN communication.
The NUC131U platform is based on AEC-Q100 grade 2 qualified NuMicro®NUC131SD2AEU. For the
development flexibility, the NUC131U platform provides the extension connectors of
NUC131SD2AEU, the Arduino UNO compatible headers and able to adopt multiple power supply.
Furthermore, the Nuvoton-designed ammeter connector can measure the power consumption
instantly, which is essential for the prototype evaluation. Finally yet importantly, the NUC131U platform
is implemented a CAN bus interface with an AEC-Q100 qualified high-speed CAN transceiver to
realize new CAN design.
In addition to the M031 platform, there is an attached on-board debugger and programmer “Nu-Link2-
Me”. The Nu-Link2-Me supports on-chip debugging, online and offline ICP programming via SWD
interface. The Nu-Link2-Me supports virtual COM (VCOM) port for printing debug messages on PC.
Besides, the programming status could be shown on the built-in LEDs. Lastly, the Nu-Link2-Me could
be detached from the development board and becoming a stand-alone mass production programmer.
Figure 1-1 NuMaker-NUC131U Development Board

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2 FEATURES
NuMicro®NUC131SD2AEU microcontroller with function compatible with:
NUC131SC2AEU
NUC131SD2AEU extension connectors
Arduino UNO compatible extension connectors
Ammeter connector for measuring the microcontroller’s power consumption
AEC-Q100 qualified high-speed CAN transceiver
Flexible board power supply:
External VDD power connector
Arduino UNO compatible extension connector Vin
USB connector on NUC131U platform
ICE USB connector on Nu-Link2-Me
On-board Nu-Link2-Me debugger and programmer
Debug through SWD interface
On-line/off-line programming
Virtual COM port function

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3 HARDWARE CONFIGURATION
Front View3.1
ICE USB Connector
VCOM Switch
Reset Button
ICE Status LED
Off-line Program Button
USB PWR Connector
Power LED
PB14 LED
VDD Switch
NUC131SD2AEU NUC131SD2AEU Extension Connectors
Arduino UNO Compatible Extension Connectors
External VDD Connector
Nu-Link2-Me
Ammeter
ICE Chip: M48SSIDAE
External VSS Connector
NUC131U Platform
External VREF Connector
CAN Transceiver
Figure 3-1 Front View of NuMaker-NUC131U
Figure 3-1 shows the main components and connectors from the front side of NuMaker-NUC131U.
The following lists components and connectors from the front view:
Target chip: NUC131SD2AEU (U1)
USB PWR Connector (J2)
Arduino UNO Compatible Extension Connectors (NU1, NU2, NU3, NU4)
NUC131SD2AEU Extension Connectors (JP3, JP4, JP5 and JP6)
CAN Transceiver TJA1057GT/3 (U10)
External VDD Power Connector (JP1)
External VSS Power Connector (JP2)
External VREF Connector (VREF1)
VDD Switch (SW2)
Ammeter Connector (AMMETER)
Reset Button (SW1)
Power LED and PB14 LED (LEDG1 and LEDR1)
Nu-Link2-Me
VCOM Switch (ICESW2)
ICE Chip: M48SSIDAE (ICEU2)
ICE USB Connector (ICEJ3)
ICE Status LED (ICES0,ICES1, ICES2, ICES3)
Off-line Program Button (ICESW1)

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Rear View3.2
Figure 3-2 shows the main components and connectors from the rear side of NuMaker-NUC131U.
The following lists components and connectors from the rear view:
Nu-Link2-Me
MCUVCC Power Switch (ICEJPR1)
ICEVCC Power Switch (ICEJPR2)
ICEVCC Power Switch
MCUVCC Power Switch
Figure 3-2 Rear View of NuMaker-NUC131U

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Extension Connectors3.3
Table 3-1 presents the extension connectors.
Connector
Description
JP3, JP4, JP5 and JP6
Full pins extension connectors on the NuMaker-NUC131U.
NU1, NU2, NU3 and NU4
Arduino UNO compatible pins on the NuMaker-NUC131U.
Table 3-1 Extension Connectors
3.3.1 Pin Assignment for Extension Connectors
The NuMaker-NUC131U provides the NUC131SD2AEU onboard and extension connectors (JP3, JP4,
JP5 and JP6). The Figure 3-3 shows the NUC131SD2AEU extension connectors.
JP3
Pin1 ~ Pin16
JP6
Pin48 ~ Pin64
JP5 Pin16 ~ Pin32
JP4 Pin32 ~ Pin48
Figure 3-3 NUC131SD2AEU Extension Connectors

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Header
NUC131SD2AEU
Pin No.
Function
JP3
JP3.1
JP3.2
1
PB.14/INT0
JP3.3
JP3.4
2
PB.13
JP3.5
JP3.6
3
PB.12/CLKO/BPWM1_CH3
JP3.7
JP3.8
4
PF.5/I2C0_SCL/PWM1_CH5
JP3.9
JP3.10
5
PF.4/I2C0_SDA/PWM1_CH4
JP3.11
JP3.12
6
PA.11/I2C1_SCL/PWM1_CH3
JP3.13
JP3.14
7
PA.10/I2C1_SDA/PWM1_CH2
JP3.15
JP3.16
8
PA.9/I2C0_SCL/UART1_nCTS
JP3.17
JP3.18
9
PA.8/I2C0_SDA/UART1_nRTS
JP3.19
JP3.20
10
PB.4/UART1_RXD
JP3.21
JP3.22
11
PB.5/UART1_TXD
JP3.23
JP3.24
12
PB.6/UART1_nRTS
JP3.25
JP3.26
13
PB.7/UART1_nCTS
JP3.27
JP3.28
14
LDO_CAP
JP3.29
JP3.30
15
VDD
JP3.31
JP3.32
16
VSS
JP5
JP5.1
JP5.2
17
PB.0/UART0_RXD
JP5.3
JP5.4
18
PB.1/UART0_TXD
JP5.5
JP5.6
19
PB.2/UART0_nRTS/TM2_EXT/PWM1_BRAKE1/TM2
JP5.7
JP5.8
20
PB.3/UART0_nCTS/TM3_EXT/PWM1_BRAKE0/TM3
JP5.9
JP5.10
21
PD.6/CAN0_RXD/BPWM1_CH1
JP5.11
JP5.12
22
PD.7/CAN0_TXD/BPWM1_CH0
JP5.13
JP5.14
23
PD.14/UART2_RXD/BPWM0_CH5
JP5.15
JP5.16
24
PD.15/UART2_TXD/BPWM0_CH4
JP5.17
JP5.18
25
PC.3/SPI0_MOSI0/BPWM0_CH3
JP5.19
JP5.20
26
PC.2/SPI0_MISO0/BPWM0_CH2
JP5.21
JP5.22
27
PC.1/SPI0_CLK/BPWM0_CH1
JP5.23
JP5.24
28
PC.0/SPI0_SS0/BPWM0_CH0
JP5.25
JP5.26
29
PE.5/PWM0_CH5/TM1/TM1_EXT
JP5.27
JP5.28
30
PB.11/TM3/PWM0_CH4
JP5.29
JP5.30
31
PB.10/TM2
JP5.31
JP5.32
32
PB.9/TM1
JP4
JP4.1
JP4.2
33
PC.11/PWM1_BRAKE1
JP4.3
JP4.4
34
PC.10/PWM1_BRAKE0
JP4.5
JP4.6
35
PC.9/PWM0_BRAKE1

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JP4.7
JP4.8
36
PC.8/PWM0_BRAKE0
JP4.9
JP4.10
37
PA.15/PWM0_CH3
JP4.11
JP4.12
38
PA.14/PWM0_CH2
JP4.13
JP4.14
39
PA.13/PWM0_CH1/UART5_TXD
JP4.15
JP4.16
40
PA.12/PWM0_CH0/UART5_RXD
JP4.17
JP4.18
41
PF.7/ICE_DAT
JP4.19
JP4.20
42
PF.6/ICE_CLK
JP4.21
JP4.22
43
AVSS
JP4.23
JP4.24
44
PA.0/ADC_CH0/I2C1_SCL/UART5_TXD/PWM0_CH4
JP4.25
JP4.26
45
PA.1/ADC_CH1/I2C1_SDA/UART5_RXD/PWM0_CH5
JP4.27
JP4.28
46
PA.2/ADC_CH2/UART3_TXD/PWM1_CH0
JP4.29
JP4.30
47
PA.3/ADC_CH3/UART3_RXD/PWM1_CH1
JP4.15
JP4.32
48
PA.4/ADC_CH4
JP6
JP6.1
JP6.2
49
PA.5/ADC_CH5/UART3_RXD
JP6.3
JP6.4
50
PA.6/ADC_CH6/UART3_TXD
JP6.5
JP6.6
51
PA.7/ADC_CH7/VREF
JP6.7
JP6.8
52
AVDD
JP6.9
JP6.10
53
PC.7/UART4_RXD/I2C0_SCL/PWM0_BRAKE1
JP6.11
JP6.12
54
PC.6/UART4_TXD/I2C0_SDA/PWM0_BRAKE0
JP6.13
JP6.14
55
PC.15
JP6.15
JP6.16
56
PC.14
JP6.17
JP6.18
57
PB.15/INT1/TM0/TM0_EXT/BPWM1_CH5
JP6.19
JP6.20
58
PF.0/XT1_OUT
JP6.21
JP6.22
59
PF.1/XT1_IN
JP6.23
JP6.24
60
nRESET
JP6.25
JP6.26
61
VSS
JP6.27
JP6.28
62
VDD
JP6.29
JP6.30
63
PF.8/CLKO/BPWM1_CH4
JP6.15
JP6.32
64
PB.8/TM0/STADC/CLKO/BPWM1_CH2
Table 3-2 NUC131SD2AEU Full-pin Extension Connectors and GPIO Function List

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3.3.2 Arduino UNO Compatible Extension Connectors
Figure 3-4 shows the Arduino UNO compatible extension connectors.
MISO CLK RESET SS
PC.2 PC.1 nRESET PB.10
5V MOSI GND GPIO
VDD PC.3 VSS PB.13
UART5_RXD PWM0_CH0 PA.12 D0
UART5_TXD PWM0_CH1 PA.13 D1
I2C1_SDA PWM1_CH2 PA.10 D2
I2C1_SCL PWM1_CH3 PA.11 D3
PWM0_CH2 PA.14 D4
PWM0_CH3 PA.15 D5
PWM0_CH4 PB.11 D6
PWM0_CH5 PE.5 D7
BPWM1_CH3 PB.12 D8
BPWM1_CH5 PB.15 D9
SPI0_SS0 BPWM0_CH0 PC.0 D10
SPI0_MOSI0
BPWM0_CH3 PC.3 D11
SPI0_MISO0
BPWM0_CH2 PC.2 D12
SPI0_CLK BPWM0_CH1 PC.1 D13
VSS VSS
PA.7 VREF
I2C0_SDA PA.8 SDA
I2C0_SCL PA.9 SCL
VIN
VSS
VSS
5V
3V
RST
IOREF VDD
NC
A5 PA.0 ADC_CH0 I2C1_SCL UART5_TXD
A4 PA.1 ADC_CH1 I2C1_SDA UART5_RXD
A3 PA.2 ADC_CH2 UART3_TXD
A2 PA.3 ADC_CH3 UART3_RXD
A1 PA.4 ADC_CH4
A0 PA.5 ADC_CH5
Figure 3-4 Arduino UNO Compatible Extension Connectors

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Header
NuMaker-NUC131U
Header
NuMaker-NUC131U
Compatible to
Arduino UNO
GPIO Pin of
NUC131SD2AEU
Compatible to
Arduino UNO
GPIO Pin of
NUC131SD2AEU
N
U
3
NU3.1
D0
PA.12
N
U
2
NU2.6
A5
PA.0
NU3.2
D1
PA.13
NU2.5
A4
PA.1
NU3.3
D2
PA.10
NU2.4
A3
PA.2
NU3.4
D3
PA.11
NU2.3
A2
PA.3
NU3.5
D4
PA.14
NU2.2
A1
PA.4
NU3.6
D5
PA.15
NU2.1
A0
PA.5
NU3.7
D6
PB.11
N
U
1
NU1.8
VIN
-
NU3.8
D7
PE.5
NU1.7
VSS
N
U
4
NU4.1
D8
PB.12
NU1.6
VSS
NU4.2
D9
PB.15
NU1.5
5V
NU4.3
D10
PC.0
NU1.4
3V
NU4.4
D11
PC.3
NU1.3
RST
nRESET
NU4.5
D12
PC.2
NU1.2
IOREF
VDD
NU4.6
D13
PC.1
NU1.1
NC
-
NU4.7
VSS
VSS
NU4.8
VREF
PA.7
NU4.9
SDA
PA.8
NU4.10
SCL
PA.9
Table 3-3 Arduino UNO Extension Connectors and NUC131SD2AEU Mapping GPIO List

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Power Supply Configuration3.4
The NuMaker-NUC131U is able to adopt multiple power supply. External power source include NU1
Vin (7 V to 12 V), VDD (depends on target chip operating voltage), and PC through USB connector.
By using switches and voltage regulator, multiple power domains can be created on the NuMaker-
NUC131U.
3.4.1 VIN Power Source
Table 3-4 presents the Vin power source.
Connector
Net Name in
Schematic
Description
NU1 pin8
NU1_VIN
Board external power source, with voltage range from 7
V to 12 V. The voltage regulator UP2 converts the NU1
pin8 input voltage to 5 V and supplies it to NU1_5VCC.
Table 3-4 Vin Power Source
3.4.2 5 V Power Sources
Table 3-5 presents the 5 V power sources.
Connector
Net Name in
Schematic
Description
ICEJ3
USB_HS_VBUS
ICE USB connector supplies 5 V power from PC to
NUC131U platform and Nu-Link2-Me.
J2
USB_VBUS
USB connector on NuMaker-NUC131U supplies 5 V
power from PC to NUC131U platform and Nu-Link2-Me.
NU1 pin5
NU1_5VCC
ICEJ3, J2 or NU1 pin8 supplies 5 V power to NU1 pin5.
NU1 pin5 supplies 5 V power to target chip or Arduino
adapter board.
Table 3-5 5 V Power Sources

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3.4.3 3.3 V Power Sources
Table 3-6 presents the 3.3 V power sources.
Voltage Regulator
5 V Source
Description
ICEUP1
USB_HS_VBUS
ICEUP1 converts USB_HS_VBUS to 3.3 V and supplies
3.3 V to NUC131U platformor ICE chip.
UP1
USB_VBUS
UP1 converts USB_VBUS to 3.3 V and supplies 3.3 V
to NUC131U platform.
Note: SW2.2 (NU1 3VCC) should be switched to ON.
UP1
NU1_5VCC
UP1 converts NU1_5VCC to 3.3 V and supplies 3.3 V to
NUC131U platform.
Note: SW2.2 (NU1 3VCC) should be switched to ON.
Table 3-6 3.3 V Power Sources
3.4.4 1.8 V Power Sources
Table 3-7 presents the 1.8 V power source.
Voltage Regular
5V Source
Description
ICEUP2
USB_HS_VBUS
ICEUP2 converts USB_HS_VBUS to 1.8 V and supplies
1.8 V to NUC131U platformor ICE chip.
Table 3-7 1.8 V Power Sources
3.4.5 Power Connectors
Table 3-8 presents the power connectors.
Connector
Description
JP1
VDD connector on the NuMaker-NUC131U.
JP2
VSS connector on the NuMaker-NUC131U.
Table 3-8 Power Connectors

NuMaker-NUC131U
May. 07, 2020 Page 18 of 46 Rev 1.00
NUMAKER-NUC131U USER MANUAL
Maker Nu-mbed NUC472 User Manual
3.4.6 USB Connectors
Table 3-9 presents the USB connector.
Connector
Description
ICEJ3
ICE USB connector on Nu-Link2-Me for power supply, debugging and
programming from PC.
J2
USB FS connector on NuMaker-NUC131U for power supply.
Table 3-9 USB Connectors
3.4.7 Power Switches
Table 3-10 presents the power switches.
Switch
Description
ICEJPR1
Configures the target chip operating voltage at 1.8 V / 3.3 V / 5 V.
ICEJPR2
Configures the ICE chip operating voltage at 1.8 V / 3.3 V.
SW2
Configures the target chip operating voltage at 3.3 V / 5 V.
Table 3-10 Power Switches

NuMaker-NUC131U
May. 07, 2020 Page 19 of 46 Rev 1.00
NUMAKER-NUC131U USER MANUAL
Maker Nu-mbed NUC472 User Manual
3.4.8 Power Supply Models
External Power Supply through Nu-Link2-Me to Target Chip3.4.8.1
The external power supply source on Nu-Link2-Me is shown in Figure 3-5.
ICE USB Connector (ICEJ3)
Nu-Link2-Me
Figure 3-5 External Power Supply Sources on Nu-Link2-Me
To use ICEJ3 on Nu-Link2-Me as external power supply source, please follow the below steps:
1. Solder the resistor on ICEJPR1 (MCUVCC) depends on the target chip operating voltage.
2. Solder the resistor on ICEJPR2 (ICEVCC) depends on the ICE chip operating voltage.
3. Switch the SW2 to OFF.
4. Connect the external power supply to ICEJ3.
Table 3-11 presents all power models when supplies external power through Nu-Link2-Me. The Nu-
Link2-Me external power sources are highlighted in yellow.
Model
Target
Chip
Voltage
ICEJ3
ICEJPR1
(MCUVCC)
Selection [1]
ICEJPR2
(ICEVCC)
Selection [2]
ICE
Chip
Voltage
SW2
Selection
J2
Vin
JP1
1
1.8 V
Connect
to PC
1.8 V
1.8 V
1.8 V
Off
X
X
1.8 V
output
2
3.3 V
Connect
to PC
3.3 V (default)
3.3 V (default)
3.3 V
Off
X
X
3.3 V
output
3
5 V
Connect
to PC
5 V
3.3 V (default)
3.3 V
Off
X
X
5 V
output
Note:
1. 0 Ω should be soldered between ICEJPR1’s MCUVCC and 1.8 V / 3.3 V / 5 V.
2. 0 Ω should be soldered between ICEJPR2’s ICEVCC and 1.8 V / 3.3 V.
3. X: Unused.
Table 3-11 Supply External Power through Nu-Link2-Me

NuMaker-NUC131U
May. 07, 2020 Page 20 of 46 Rev 1.00
NUMAKER-NUC131U USER MANUAL
Maker Nu-mbed NUC472 User Manual
External Power Supply through NUC131U platform to Target Chip3.4.8.2
The external power supply sources on NUC131U platform are shown in Figure 3-6.
USB Power Connector (J2)
NU1 pin8 (Vin)
External VDD Connector (JP1)
External VSS Connector (JP2)
Figure 3-6 External Power Supply Sources on NUC131U platform
To use Vin or J2 as external power supply source, please follow the below steps:
1. Switch the SW2 depends on the target chip operating voltage.
2. Remove the resistor on ICEJPR1 (MCUVCC).
3. Solder the resistor on ICEJPR2 (ICEVCC) depends on the ICE chip operating voltage.
4. Connect the external power supply to Vin or J2.
To use JP1 as external power supply source, please follow the below steps:
1. Switch the SW2 to OFF.
2. Remove the resistor on ICEJPR1 (MCUVCC).
3. Solder the resistor on ICEJPR2 (ICEVCC) depends on the ICE chip operating voltage.
4. Connect ICEJ3 to PC.
5. Connect the external power supply to JP1.
To use Vin or J2 as external power supply source with Nu-Link2-Me detached from NuMaker-
NUC131U, please follow the below steps:
1. Switch the SW2 depends on the target chip operating voltage.
2. Detach the Nu-Link2-Me from NuMaker-NUC131U.
3. Connect the external power supply to Vin or J2.
To use JP1 as external power supply source with Nu-Link2-Me detached from NuMaker-NUC131U,
please follow the below steps:
1. Switch the SW2 to OFF.
2. Detach the Nu-Link2-Me from NuMaker-NUC131U.
3. Connect the external power supply to JP1.