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9 years ago.
Problem detecting mbed as a serial com port
I have a custom designed board using a NXP LPC1768 and communicates with the computer via USB. The mbed device is recognized as a 'Portable Device' and shows up as a mass storage device in Computer.
I am having trouble communicating with the board and I believe the main problem at this point is having Windows recognize the device as an emulated serial connection instead of a portable device.
I attempted to install the serial driver (mbedWinSerial_16466) listed on the Windows serial configuration page (http://developer.mbed.org/handbook/Windows-serial-configuration) but the application fails to install the driver saying "The driver could not be installed. No mbed Microcontrollers were found".
I extracted the .inf files from the exe in an attempt to force-feed the drivers to the device in device manager but it refuses to install stating no compatible software drivers were found for the device. I also tried adding the hardware/product ID of the mbed controller to the .inf file but to no avail.
The device shows as the following: idVendor: 0x0703 idProduct: 0x0104 bcdDevice: 0x0001 iManufacturer: 0x01 0x0009: "mbed.org" iProduct: 0x02 0x0009: "Mbed MSD" iSerialNumber: 0x03 0x0009: "0123456789" bNumConfigurations: 0x01
The same process was repeated on another computer (Windows 7 x64) with the same results.
Are there any alternative ways to install the drivers for the mbed device?
1 Answer
9 years ago.
Does your custom PCB match the schematic for USB IF_D+ and IF_D-? (it seems like it does because Windows detects id's) http://developer.mbed.org/media/uploads/chris/mbed-005.1.pdf
At the time of installing the software driver is the 1768 MCU powered up and plugged into the PC USB port? (I had this issue)
I wonder if there is firmware to be loaded first via drag and drop to the LPC1768 mass storage device? http://developer.mbed.org/handbook/Firmware-LPC1768-LPC11U24
Thank you for your response. I have verified the design of the PCB matches the schematic in your link. (Inserted image below):
http://i.imgur.com/O3gFL9d.png
When the mbed device is connected to the computer via USB, windows will automatically install the portable device drivers. The mbed device is powered on and the corresponding 'portable device' in Windows is recognized when I attempt to install the serial drivers (mbedWinSerial_16466).
In reference to this forum post, http://developer.mbed.org/forum/mbed/topic/4672/, I tried disconnecting the 5V power source and allowed the USB cable to power the mbed controller. Both methods produced the same result.
I would try to install the latest firmware but I noticed something else strange about the mbed controller. The mass storage device that Windows detects when the mbed controller is connected is only 20 KB while the datasheet shows it should have 512 KB of flash memory. In addition, instead of finding a MBED.htm file in the mass storage device, I find a README.TXT file saying "Hello from Mbed! USB MSD demo".
posted by 16 Apr 2015You could check out this question: http://developer.mbed.org/questions/7127/How-I-can-make-MBED-Program-To-Custom-LP/
I remember reading that the LPC1768 has an external chip for mass storage. Does your design have this extra memory chip? see: http://developer.mbed.org/users/chris/notebook/prototype-to-hardware/
posted by 16 Apr 2015