NXP LPCXPRESSO55S69¶

Overview¶

The LPCXpresso55S69 development board provides the ideal platform for evaluation of and development with the LPC55S6x MCU based on the Arm® Cortex®-M33 architecture. The board includes a high performance onboard debug probe, audio subsystem, and accelerometer, with several options for adding off-the-shelf add-on boards for networking, sensors, displays, and other interfaces.

Hardware¶

LPC55S69 dual core Arm Cortex-M33 microcontroller running at up to 100 MHz
Onboard, high-speed USB, Link2 debug probe with CMSIS-DAP and SEGGER J-Link protocol options
UART and SPI port bridging from LPC55S69 target to USB via the onboard debug probe
Hardware support for external debug probe
3 x user LEDs, plus Reset, ISP (3) and user buttons
Micro SD card slot (4-bit SDIO)
NXP MMA8652FCR1 accelerometer
Stereo audio codec with line in/out
High and full speed USB ports with micro A/B connector for host or device functionality
MikroEletronika Click expansion option
LPCXpresso-V3 expansion option compatible with Arduino UNO
PMod compatible expansion / host connector

For more information about the LPC55S69 SoC and LPCXPRESSO55S69 board, see:

Supported Features¶

The lpcxpresso55s69 board configuration supports the following hardware features:

Interface	Controller	Driver/Component
NVIC	on-chip	nested vector interrupt controller
SYSTICK	on-chip	systick
IOCON	on-chip	pinmux
GPIO	on-chip	gpio
I2C	on-chip	i2c
SPI	on-chip	spi
USART	on-chip	serial port-polling
WWDT	on-chip	windowed watchdog timer
TrustZone	on-chip	Trusted Firmware-M
ADC	on-chip	adc
CLOCK	on-chip	clock_control

The default configuration file boards/arm/lpcxpresso55s69/lpcxpresso55s69_cpu0_defconfig only enables the first core.

Other hardware features are not currently enabled such as dual core or secure/non-secure.

Targets available for this board are:

lpcxpresso55s69_cpu0 secure (S) address space for CPU0
lpcxpresso55s69_ns non-secure (NS) address space for CPU0
lpcxpresso55s69_cpu1 CPU1 target, NS only

CPU0 is the only target that can run standalone. NS target for CPU0 does not work correctly without a secure image enabling it. CPU1 does not work without CPU0 enabling it.

Connections and IOs¶

The LPC55S69 SoC has IOCON registers, which can be used to configure the functionality of a pin.

Name	Function	Usage
PIO0_26	SPI	SPI MOSI
PIO0_29	USART	USART RX
PIO0_30	USART	USART TX
PIO1_1	SPI	SPI SSEL
PIO1_2	SPI	SPI SCK
PIO1_3	SPI	SPI MISO
PIO1_4	GPIO	RED LED
PIO1_6	GPIO	BLUE_LED
PIO1_7	GPIO	GREEN LED
PIO1_20	I2C	I2C SCL
PIO1_21	I2C	I2C SDA

System Clock¶

The LPC55S69 SoC is configured to use the internal FRO at 96MHz as a source for the system clock. Other sources for the system clock are provided in the SOC, depending on your system requirements.

Serial Port¶

The LPC55S69 SoC has 8 FLEXCOMM interfaces for serial communication. One is configured as USART for the console and the remaining are not used.

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 does not yet 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. Please make sure you have the latest firmware for this board.

OpenSDA DAPLink Onboard Debug Probe ¶

PyOCD support for this board is ongoing and not yet available. To use DAPLink’s flash memory programming on this board, follow the instructions for updating LPCXpresso firmware.

Configuring a Console¶

Connect a USB cable from your PC to P6, and use the serial terminal of your choice (minicom, putty, etc.) with the following settings:

Speed: 115200
Data: 8 bits
Parity: None
Stop bits: 1

Flashing¶

Here is an example for the Hello World application. This example uses the J-Link Debug Host Tools as default.

# From the root of the zephyr repository
west build -b lpcxpresso55s69_cpu0 samples/hello_world
west flash

Open a serial terminal, reset the board (press the RESET button), and you should see the following message in the terminal:

***** Booting Zephyr OS v1.14.0 *****
Hello World! lpcxpresso55s69_cpu0

Building and flashing secure/non-secure with Arm® TrustZone®¶

The TF-M integration samples can be run using the lpcxpresso55s69_ns target. Next we need to manually flash the secure (tfm_s.hex) and non-secure (zephyr.hex) images wth a J-Link as follows:

JLinkExe -device lpc55s69 -if swd -speed 2000 -autoconnect 1
J-Link>loadfile build/tfm/install/outputs/LPC55S69/tfm_s.hex
J-Link>loadfile build/zephyr/zephyr.hex

NOTE: At present, the LPC55S69 doesn’t include support for the MCUBoot bootloader. We need to reset the board manually after flashing the image to run this code.

Debugging¶