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8 years, 9 months ago.
many systems wont boot with large descriptor (>64 byte)
each case is different, but using the standard Force Feedback Joystick descriptor with this USBDevice library many of our systems refuse to boot while device is connected.
if it is connected after system has booted everything is working normally.
Turning off USB Legacy 2.0 support in BIOS options seems to help in some cases, but this is not ideal because then the keyboard will not work in BIOS after.
Seems to be some issue transferring the descriptor to the BIOS.
The descriptor I am using is here: http://www.microchip.com/forums/FindPost/378772
Any idea what I could change to resolve this?
I have created a latch system that sends a simple descriptor then resets the mbed and loads the advanced descriptor.. but this is a bit too hacky and I'm considering switching to a different board, because I have had success using the same descriptor on other platforms.
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8 years, 9 months ago.
It has been a while since I worked on the USB Joystick library listed here. I dont recall seeing your problem with that lib, have you tried the code on your machine.
I had originally used the USBJoystick example and had a similar problem, thats why I've migrated to the official USB Device stack hoping to resolve the issue, but the problem still exists.
I am currently looking into LPCXpresso IDE with nxpUSBlib examples. Apparently it should work with the mbed LPC1768 but I am having problems getting the example devices to even be detected by the OS, as if the pins are not compatible, but that should not be the case.
the NXP community has many more USB device stack libraries on offer, rather than the one or two for mbed.
Even if the nxp usb library works with this descriptor, implementing it with my current code is a bit of a monumental task, so I'm hanging on hoping this Library can still be fixed.
posted by 14 Jul 2015