Search found 162 matches

by Grendel
Thu Mar 29, 2007 2:41 am
Forum: V-USB
Topic: 68 ohm resistors
Replies: 3
Views: 7377

I used 82 ohm resistors in my project w/o a problem.
by Grendel
Tue Mar 13, 2007 3:00 am
Forum: V-USB
Topic: Elektor AVR-USB-Artikel
Replies: 4
Views: 7402

Da ist noch ein Artikel -- Universeller USB-Treiber . Nochmals 1.30 Euronen.. Das Entwickeln eines Systems mit USB-Schnittstelle ist sicher eine interessante Aufgabe wenn da nur nicht der Treiber wäre. Mit dem Schreiben dieses unumgänglichen Programms tun sich viele Hardware-Spezialisten schwer. Die...
by Grendel
Tue Feb 13, 2007 11:54 pm
Forum: V-USB
Topic: [long] IR mouse problem
Replies: 17
Views: 20179

How big is ir.data[] dimensioned ? I could see that overflowing if it's smaller than 253.
by Grendel
Tue Feb 13, 2007 11:42 pm
Forum: V-USB
Topic: [long] IR mouse problem
Replies: 17
Views: 20179

.bss segment crossing a 256b page boundary maybe ?
by Grendel
Wed Feb 07, 2007 12:41 am
Forum: V-USB
Topic: Getting started with AVR-USB
Replies: 37
Views: 36686

To compile AVR firmware you'll also need WinAVR. As for how to use libusb, check out the AVRUSBBoot project.
by Grendel
Sun Feb 04, 2007 1:22 am
Forum: V-USB
Topic: "Unknown Device" detected in WinXP
Replies: 3
Views: 6283

In windows an unknown, malf device means that the speed resitor is active but the device is not reacting or sending garbage. Invalid usbconfig.h entries or fuse/config bits set wrong are a good source for this error (assuming the hardware is wired right.)
by Grendel
Sat Feb 03, 2007 10:49 am
Forum: V-USB
Topic: Overclocked microcontroller and other questions...
Replies: 2
Views: 5120

Re: Overclocked microcontroller and other questions...

I still have a AT89C55WD-24PC spare part but I think I can not use this chip because of the internal tact divider, is this true? Depends, usually the internal clocks have more tolerance than the USB spec allows (+/- 1.5% for low speed devices.) Use of a crystal oscilator is strongly recommended. Wh...
by Grendel
Wed Jan 31, 2007 2:01 am
Forum: V-USB
Topic: [long] IR mouse problem
Replies: 17
Views: 20179

Skimming over your posts, how high are your IR interrupt frequencies ? It looks like your IRQ handler blocks further interrupts -- AVR-USB is very sensitive to IRQ latency, keep in mind there's a SOF packet sent by the host every 1ms (!): Interrupt latency: The application must ensure that the USB i...
by Grendel
Thu Jan 11, 2007 10:52 pm
Forum: V-USB
Topic: 2 Devices with one AVR
Replies: 11
Views: 15067

This is all outlined in Device Class Definition for HID 1.11 and HID Usage Tables 1.12 found on usb.org's HID Information page.. Very good reads (hint, hint .) Edit: Whatdoyouknow -- there's a standard controller for magic carpets.. 5.7 Miscellaneous Simulation Devices Magic Carpet Simulation Device...
by Grendel
Thu Jan 11, 2007 1:46 am
Forum: V-USB
Topic: 2 Devices with one AVR
Replies: 11
Views: 15067

Can be found here.
by Grendel
Sat Jan 06, 2007 1:53 am
Forum: V-USB
Topic: AVR-USB drivers, need help (USBasp programer)
Replies: 2
Views: 6141

To determine if the problem is w/ your device run usbview and check if your device sent all descriptors correctly.
by Grendel
Sat Dec 16, 2006 10:00 pm
Forum: V-USB
Topic: Using 5V AVR's with AVR-USB
Replies: 8
Views: 12143

I'm using a mega8 @ 5v in my project. I put 3V3 zeners on D-/D+, changed the series Rs to 82 and the ID R to 2k2 (w/ a 4k7 to GND). Works fine 8)