topic Re: LCP4088 QuickStart Board problem in LPC Microcontrollers

LCP4088 QuickStart Board problem

chrislynnerup — Tue, 06 Sep 2016 11:41:55 GMT

Ran into a problem. The mbed USB drive disappeared from the computer, and I cant seem to get it back.

I've tried everything (I think).

I've tried switching cables, switching computer, switching USB port. Did several reboots. Tried the reset button - insert usb cable - release reset button. I've removed mbed from portable devices in hopes of it getting reinstalled after i plug it in again. I've deactivated all USB ports and reactivated them again.

Nothing seems to work.

All I get is two blue LED lights (LED3 and LED4) that is permanently turned on. Cant do anything else and Im sorta out of ideas.

Re: LCP4088 QuickStart Board problem

andersrosvall — Tue, 06 Sep 2016 12:28:53 GMT

Hi Chris,

If you do not get any USB drive at all (MBED or CRP_DISABLD), then the USB interface is damaged.

If you get a CRP_DISABLD drive, then you have accidentally erased the HDK firmware. Check here to download the latest HDK firmware (nowadays called DAPLink): LPC4088 Updating the DAPLink interface | mbed

I would recommend to verify that the internal 3.3V power rail is ok. Measure between pin 1 and 42.

I also recommend to press the USB cable slightly when inserted into the LPC4088 QuickStart Board. The connector might not be firmly fixed in place. Be careful, though, so you do not break off the USB connector from the PCB.

Kind Regards,

Anders from the EA Team

Re: LCP4088 QuickStart Board problem

chrislynnerup — Tue, 06 Sep 2016 12:42:08 GMT

Hi Anders.

I suppose you mean between pin 1 and 44? If so, then I get 3,3V

It must be the USB then, since I dont get either the normal drive or CRP_DISABLD.

Is there a way to either fix that, or maybe set up the board to use the other USB, located under the ethernet connection.

Re: LCP4088 QuickStart Board problem

andersrosvall — Tue, 06 Sep 2016 13:09:51 GMT

Hi again Chris,

Yes, I meant between pin 1 and 44. Sorry for the confusion.

Anyways, there is no way to switch USB interface. The USB interface in question is the one connected to the on-board debug MCU (LPC11U35). The other USB interface is connected to the LPC4088.

You should also check so that the debug interface is actually powered. There is a small jumper (1.27mm pitch) in the lower right corner (if the Ethernet connector on the LPC4088 QuickStart board is pointing from you). Double-check so that this jumper is actually inserted. Else the debug interface is powered down (and you would get the exact same behavior as you describe - no USB enumeration).

Kind Regards,

Anders from the EA Team

Re: LCP4088 QuickStart Board problem

chrislynnerup — Tue, 06 Sep 2016 13:27:05 GMT

If the small jumper is the "tall" black one, that I can lift off, then yes its still attached.

Re: LCP4088 QuickStart Board problem

andersrosvall — Tue, 06 Sep 2016 14:24:21 GMT

Ok, then it seems like your USB interface has been damaged; USB connector or LPC11U35 MCU.

It is typically not possible to repair.

Kind Regards,

Anders from EA Team

Re: LCP4088 QuickStart Board problem

andersrosvall — Tue, 06 Sep 2016 21:25:05 GMT

Hi again Chris,

I forgot to write that you should contact our support, so we can have a look at the board and see what can be done.

Kind Regards,

Anders from EA Team.