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USBDroid and Practical Arduino Virtual USB keyboard tutorial

Posted: Fri Apr 06, 2012 2:03 am
by Curoch
Hi All

I'm new at this - but I've been trying to get the Virtual USB Keyboard example from the book "Practical Arduino" working on the USB Droid for a few days now.

I built everything according to the schematic and uploaded the example code from the rancid bacon website. It appears to not work - there appears to be multiple issues.

1. Setting DIO11 to input and latching it high does not work as expected. The output from this pin in its high state is only 0.4V. This results in the example code detecting button 11 as permanently pressed. I tried another USBDroid, and it behaves identically, so it isn't a broken hardware issue.

2. I commented out the code corresponding to this pin uncovered an enumeration error on the host machine - the error messages are as follows:

usb 2-3: new low speed USB device using ohci_hcd and address 30
usb 2-3: device descriptor read/64, error -71

Any ideas? Thanks!

Re: USBDroid and Practical Arduino Virtual USB keyboard tuto

Posted: Sat Apr 07, 2012 7:25 am
by Curoch
Hey all

One problem solved - the Zener Diodes that I was given by the shop assistant were the wrong type, which probably was resulting in the USB incompatibility errors.

However, I still am unable to pin down the problem with Pin 11.

:D

Re: USBDroid and Practical Arduino Virtual USB keyboard tuto

Posted: Sun Apr 08, 2012 11:22 am
by jonoxer
Perhaps the D11 pin is being biased by the connection to the USB host chip. On specialised boards like the USBDroid with extra on-board peripherals it's best to avoid the pins that have been special-purposed, which we indicate on the PCB using a heavy black border around those pins.

Could you give it a try with a different digital I/O pin that's not connected to anything else?
--
Jon

Re: USBDroid and Practical Arduino Virtual USB keyboard tuto

Posted: Mon Apr 09, 2012 10:50 pm
by Curoch
Thanks for the reply - I will do just that, as soon as the correct Zener Diodes come in :D

Regards

Curoch