Stephan Noller

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9 years, 2 months ago.

Board will disconnect after hex upload

Hi, i have the BLE nano and i can do a firmware update (on MacOS 10.9.1). But when i want to copy the blinky example or any other file or .hex onto the MBED Device it will try to copy but then disconnect with the typical OS-warning that i should eject the medium before unplugging. Tried to go through arduino ide, but didn't work either. Any idea? Thanks, S

Question relating to:

Last updated: 27 Aug 2020
BLE Nano is the smallest Bluetooth 4.1 Low Energy (BLE) development board in the market. The core is Nordic nRF51822 (an ARM Cortex-M0 SoC plus BLE capability) running at 16MHz …

8 Answers

karl rathbone
9 years, 2 months ago.

Have you soldered the nano onto the pins? This may fix the issue.

Yes, of course. I guess a firmware update would not have been possible without soldering, too...

posted by Stephan Noller 14 Feb 2015

Firmware did update on mine strangely enough

posted by karl rathbone 14 Feb 2015
wen huang lin
7 years, 8 months ago.

I have the same problem. Does anyone solve this issue? Thanks!

Patrick Mueller
8 years, 11 months ago.

I have the same problem both with Windows and with OS X Yosemite 10.10.3. I cannot upload any file onto the MBED drive. Apart from some better documentation I feel there are some bugs to solve.

Philp Insull
8 years, 8 months ago.

I was having some difficulty making blinky appear to work.(HP laptop, Windows 7) I think part of the confusion is that the MBED drive gets dumped once you load the blinky file onto it. Looks like you just unplug and replug the USB connection and then operation begins. I wasn't sure what I was doing wrong It turns out that despite all appearances it was working. I had not realised that the led on the Nano board is acutally on its UNDERSIDE !!

How can you delete the program file, as it does not show up in the directory?

So that seems to work fine...what next....? I guess I should try to edit source for blinky and change flash rate at least.

Further, if I next get the iOS RedBear App, what file needs to be loaded onto the Nano for it to work, or does it operate directly somehow? I am completely new to BLE so forgive if I am asking wrong question. Are the buttons/pins/sliders reconfigurable within that App? Any guidance around?

Tim Barry
9 years ago.

I have the same problem. Are you suggesting soldering the nano onto the MK20 is the only way to solve this? Not a very good solution if you've got more than one Nano and only one programmer. Has anyone managed to solve this without solder?

I don't think it's required to solder the two pieces together as other folks don't seem to be doing that. I do think it's normal that it disconnects after upload, but I'm not 100% sure.

posted by John Robeson 19 Jul 2015

yep, it does disconnect, but then reconnects.

posted by John Robeson 20 Jul 2015
Josh Rodriguez
8 years, 1 month ago.

I am having this issue as well. Both windows and mac has given this problem so it clearly has to do with the device. All pins are soldered. This is disappointing. I would hope that RedBear has something to say about this.

You can use OpenOCD to burn firmware if you have any problem to use drag & drop method.

openocd -f interface/cmsis-dap.cfg -f target/nrf51.cfg -c "program FIRMWARE.hex exit reset verify"

posted by Danny Poon 29 Mar 2016
Erik -
8 years, 1 month ago.

This is intended behavior on all except the two original mbeds (LPC1768 and LPC11u24). This is supposed to happen since they don't have memory to store old files, and disconnecting is the only way to tell your OS that the file is gone and there is space for a new file.

So once I copy a .hex file to the mk20 with the nano attached to it, it disconnects, I just have to assume that the .hex was transferred to the nano successfully and that the program I wrote will just run once power is provided to the nano?

posted by Josh Rodriguez 22 Mar 2016

After disconnecting it should reconnect, if there is no fail.txt it should have gone correctly. (Note: I don't have this device myself, but thats how it works for the others).

And yes, after that you got to assume it works. Obviously it is handy to have something to indicate it is succesful (such as blinking an LED), and not code which directly enters sleep mode for half an hour.

posted by Erik - 22 Mar 2016

This reads like the behavior I'd expect from a device with a "USB bootloader". I think it was in the manual for the LPC11U24 that you could program the chip (non MBED) by USB but the loader only pretended to be a mass storage device, and it just wrote the sectors to flash in the order they were transferred.

posted by Oliver Broad 24 Mar 2016

Exactly. The LPC1768/LPC11u24 mbeds (so not the LPC11u24 ROM bootloader, but the mbed model) has a memory chip and is really a USB flash drive. The other ones only pretend to be one, and immediatly write to the target's flash memory.

posted by Erik - 24 Mar 2016
J R Moore
8 years, 11 months ago.

I have to say this isthe most badly documented and difficult to use device I have ever come across. I too get the immediate disconnect every time I try to load something to the mbed device, and cannot get the mbed driver to download using any browser from the website. I am not impressed.

yeah same , try using some download manager program , like IDM in windows . will solve problem . and i found the Mbed online compiler got issue when download hex file also , that's why when you load the hex to mbed , got error txt..... try download hex using IDM also .

posted by YUFEI JIANG 07 May 2015