NXP LPCXPRESSO51U68
Overview
The LPCXpresso51u68 development board uses an NXP LPC51U68 MCU based on an ARM CORTEX-M0+ core.
 
Hardware
- LPC51U68 M0+ running at up to 150 MHz 
- Memory - 256KB of flash memory 
- 96KB of SRAM 
 
- On-board high-speed USB based debug probe with CMSIS-DAP and J-Link protocol support, can debug the on-board LPC51U68 or an external target 
- External debug probe option 
- Tri-color LED, target reset, ISP & interrupt/user buttons for easy testing of software functionality 
- Expansion options based on Arduino UNO and PMOD™, plus additional expansion port pins 
- FTDI UART Connector 
More information can be found here:
Supported Features
The lpcxpresso51u68 support the following features:
| Interface | Controller | Driver/Component | 
|---|---|---|
| NVIC | on-chip | nested vector interrupt controller | 
| SYSTICK | on-chip | systick | 
| IOCON | on-chip | pinmux | 
| CLOCK | on-chip | clock and reset control | 
| GPIO | on-chip | gpio | 
| I2C | on-chip | i2c master/slave controller | 
| UART | on-chip | serial port-polling; serial port interrupt | 
| SPI | on-chip | SPI master | 
Other hardware is not yet supported on Zephyr.
Connections and IOs
The IOCON controller can be used to configure the LPC51U68 pins.
| Name | Function | Usage | 
|---|---|---|
| PIO0_0 | UART | USART RX | 
| PIO0_1 | UART | USART TX | 
| PIO1_10 | GPIO | GREEN LED | 
| PIO0_29 | GPIO | RED LED | 
| PIO1_9 | GPIO | BLUE_LED | 
| PIO0_25 | I2C | I2C SCL | 
| PIO0_26 | I2C | I2C SDA | 
| PIO0_18 | SPI | SPI MISO | 
| PIO0_19 | SPI | SPI SCK | 
| PIO0_20 | SPI | SPI MOSI | 
| PIO1_1 | SPI | SPI SSEL2 | 
Programming and Debugging
Build and flash applications as usual (see Building an Application and Run an Application for more details).
Configuring a Debug Probe
A debug probe is used for both flashing and debugging the board. This board is configured by default to use the LPC-Link2 CMSIS-DAP Onboard Debug Probe, however the pyOCD Debug Host Tools do not support this probe so you must reconfigure the board for one of the following debug probes instead.
LPC-Link2 J-Link Onboard Debug Probe
Install the J-Link Debug Host Tools and make sure they are in your search path.
Follow the instructions in LPC-Link2 J-Link Onboard Debug Probe to program the J-Link firmware.
Configuring a Console
Connect a USB to FTDI RX, TX & GND pins to P3 Connector.
Use the following settings with your serial terminal of choice (minicom, putty, etc.):
- Speed: 115200 
- Data: 8 bits 
- Parity: None 
- Stop bits: 1 
Flashing
Here is an example for the Hello World application.
# From the root of the zephyr repository
west build -b lpcxpresso51u68 samples/hello_world
west flash
***** Booting Zephyr OS build zephyr-v2.6.0-934-g4c438c0c7d13 *****
Hello World! lpcxpresso51u68
Debugging
Here is an example for the Hello World application.
# From the root of the zephyr repository
west build -b lpcxpresso51u68 samples/hello_world
west debug
Open a serial terminal, step through the application in your debugger, and you should see the following message in the terminal:
***** Booting Zephyr OS build zephyr-v2.6.0-934-g4c438c0c7d13 *****
Hello World! lpcxpresso51u68