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9 years, 2 months ago.

USBMSD - Device Not Recognized

I am trying to use USBMSD to give access to an SD card on SPi. I know the card is working (I can write to it the see that the file is written by inserting the card into a PC) but I cannot get the PC to recognise the USB device as a MSD. I have loaded the library and code from the handbook reference for USBMSD but Windows just reports Device Not Recognised. Has anyone had/overcome this problem?

This is on an LPC1768? Not aware of (past) issues like this for USBDevice. What kind of hardware are you using for the USB port?

posted by Erik - 27 Feb 2015

Hi Erik, thanks for responding. Yes this is LPC1768. I am connected to D+ & D- with 15K resistors to ground on both lines (but tried without as well) and connected to the PC using two wire plus ground (the mbed is powered separately). I am trying to run USBMSD_SD_HelloWorld_Mbed from the handbook page.

posted by N D 27 Feb 2015

Were you able to resolve your issue? The "Device Not Recognized" sounds a lot like a USB port hardware issue like Erik said. I've run into this issue before on different projects by having the data lines swapped, not sharing ground, and not providing the correct voltage on the USB port's pin. I would double check those things

posted by Brian Daniels 20 Mar 2015
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