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Installing U-Boot to the Embedded Artists LPC4357 Dev Kit Print


Use the procedure documented below to install the U-Boot firmware to the internal Flash of the LPC4357 on the Embedded Artists Dev Kit. Having completed the installation, the LPC4357 will run U-Boot as a primary firmware on next reset / power on.

Please note that the installation will erase whatever other firmware may be installed on your Embedded Artists LPC4357 Dev Kit at the moment and install the U-Boot image instead.

You will need the following items:

  • J-Link programmer from Segger;
  • J-Flash application from Segger installed on a Windows PC.

Please remark the following comment made in the Embedded Artists LPC4357 Dev Kit User's Manual:

Note that the LPC4357 MCU is sensitive to ESD on the JTAG port. Observe extra care around this.
Make sure the ground of the JTAG interface is connected to the OEM Base Board ground before even connecting the JTAG interface. Never have the OEM Board unpowered while the JTAG pod is powered.

Here is the installation procedure:

  1. Unplug everything from the LPC4357 kit and J-Link.
  2. Connect J-Link to J8 on the LPC4357 kit.
  3. Connect a microUSB cable between the Windows host and J25 on the LPC4357 kit.
  4. Connect J-Link to the Windows host.
  5. Start J-Flash and create a new project:
    • Select File -> New project.
    • Select Options -> Projects settings.
    • Open the CPU tab and select the Device radio button. From the list, select NXP in Manufacturer column and LPC4357_M4 in the Device column.
    • Open File -> Open data file and select u-boot.bin. When asked for Enter start address, enter 1A000000.
    • Program the Flash using Target -> Program & Verify.
    • Confirm Flash erase in a pop up window.

Next reset / power-on should bring up the U-Boot command interface to the serial console of the LPC4357. The initial U-Boot serial console interface should look as shown below:

U-Boot 2010.03-00074-cortexm-1.14.0 (May 19 2015 - 20:34:26)

CPU : LPC43xx series (Cortex-M4/M0)
Freqs: SYSTICK=144MHz,CCLK=144MHz
Board: Embedded Artists LPC4357 Dev Kit Rev A1
In: serial
Out: serial
Err: serial
Hit any key to stop autoboot: 0

Please note the on the Linux PC the LPC4357 serial console will be visible as a /dev/ttyUSBx device. The U-Boot and Linux software configures the console for 115.2 Kps operation.

There are various serial communication tools available for Linux, the most popular perhaps being kermit. kermit is a very powerful tool that can be run in interactive mode or controlled by a script. There is abandunt documentation on kermit avialable in the Internet, if you require details.

One possibility is to define on the host a shell script similar to the one below:

$ vi console-lpc4357.script

set port /dev/ttyUSB1
set speed 115200
set carrier-watch off
set flow-control none
set prefixing all

Change the file mode to make the script an executable file:

$ chmod +x console-lpc4357.script

Then run the script whenever you need to get access to the console:

$ ./console-lpc4357.script
Connecting to /dev/ttyUSB1, speed 115200
Escape character: Ctrl-\ (ASCII 28, FS): enabled
Type the escape character followed by C to get back,
or followed by ? to see other options.


To exit kermit, type Ctrl-\ and then q.