3 Mar
2013
3 Mar
'13
4:13 p.m.
On Sun, 03 Mar 2013 13:26:21 +0100
Jeremy Jongepier <jeremy(a)autostatic.com> wrote:
Dear all,
I got two cheap drumpads here that are _exactly_ the same, also on the
inside (PCB's have the same revision ID):
http://dx.com/p/portable-roll-up-usb-drum-kit-118841
But they get recognized differently, one as an USB MIDI device and the
other as an USB HID device. And when it gets recognized as a HID device
it's pretty useless because I can't hook it up easily to software that
accepts MIDI input.
I have no idea what chip it uses, but I have played a bit with Atmel
and ARM chips with built-in USB controllers. The way these work is that
the controller does the basic USB stuff in hardware, but the higher
level things, such as the USB class, are determined by the firmware. So
what you see might be a firmware bug. This sounds likely if that the
hardware is otherwise identical.
So maybe you could find a way to read out the firmware from the good
one, and flash it onto the bad one. Unfortunately, most such chips have
a code read lock bit set, so reading it may be impossible. Anyway, maybe
you could make photos of the PCB, and also see if you can decipher any
text on the chip, and post both? If we could get these to work, I might
buy one myself. For that price... :)
Is the working one otherwise okay? Are the pads pressure sensitive,
i.e. are notes played with different velocity depending depending on
how hard you hit it? (Guess not, but it would be cool)