Arm Mbed and Pelion Device Management support forum

Need confirmation of my actual circuit with LPC-1768

Hello !

I’m making a custom board with LPC-1768 chip and before test i! n real state, I would like show you my actual circuit if for you is compatible with the USB “Drake and Drop” .hex Mbed system :slight_smile:

Thanks a lot !

I believe you need DAPLink for drag and drop programming. DAPLink runs on a separate IC. If you look at mbed LPC1768 schematics, you will find a Mbed interface IC.

If you don’t need drag and drop feature, you can program your chip through JTAG/SWD interface.

Thanks,
I suppose you speaking about MBED-IF01 chip ?
I just Discover that’s now…

I need a easy reflash system :slight_smile:

Yes, that is the interface. You need DAPLink interface like that.

Or, get yourself an easy to use programmer. I have never tried this product. But, they say it can do drag and drop programming.
https://aconno.de/products/aconno-acnprog/
It may work for your needs.

Thanks,
It’s usefull but very expensive ! :slight_smile:

Drag & Drop works with .bin files. However, no additional programmer is needed to flash a .hex file to an LPC1768 MCU, except a USB to Serial converter, and it’s almost as simple as Drag & Drop. For more info have a look at Serial interface, ISP and Flash Magic.

Hi Hudakz,
It’s exactly with this page I get inspired for my circuit :slight_smile:

But I don’t understand how you program it finaly ?

You flash in the first time the chip with the SWD interface and after you program it with the simple USB port ?

If yes, that’s good for me !

Hello Gruniek,
Because programming over the serial interface is a builtin feature of LPC1768 micro-controllers the SWD interface is not needed (unless you’d like to use it for debugging). You can start to program the chip with a simple USB to serial converter connected to the chip’s serial interface (connector H3 on your schematic) from the very beginning (first time included)! Make sure you connect the converter’s Rx pin to the TXD0 pin (pin 3) on the H3 connector and the Tx pin to the RXD0 (pin 2) on the H3 connector. The converter shall also be connected to your PC over a USB cable and a proper driver should be installed on your PC which creates a virtual serial port. Then selected that virtual serial port in the Flash Magic software for programming.
Best regards, Zoltan.

A simple CH340G ttl converter can do this work ?

Yes, a CH340G should be OK.

Nice !
I need to push the reset button before flashing ?

As it is explained at Serial interface, ISP and Flash Magic:

  1. Hold down the ISP button
  2. Push and release the RESET button
  3. Release the ISP button
  4. Program the chip with Flash Magic
  5. Push and release the RESET button

Of course sorry !

Thanks !