Objective Development Forums

Interesting... It's possible that refactoring (code size improvements, but fixes) broke something. I know that it did work when it was implemented. The most reliable way to find out what's going on is analytic debugging. I would change the C code to make a trigger pulse on an I/O line when `usbRxTok...

Did you make a clean build after you defined USB_CFG_IMPLEMENT_FN_WRITEOUT? I have done a code review and think that it should work. In asmcommon.inc there are the lines: #if USB_CFG_IMPLEMENT_FN_WRITEOUT /* if we have data for endpoint != 0, set usbCurrentTok to address */ andi x3, 0xf ;[32] breq s...

It probably won't harm. I think the host is just prepared to receive remote wake.

Thanks for the hint! I've added it in the master branch on Github.

You are, of course, right. V-USB has been developed for tiny projects originally, and it's easy to rename variables or avoid particular names in tiny projects. V-USB has grown from that, as you can see, and it would be time for a major cleanup. BTW: I usually don't have the time to read the forum, j...

It has been fixed months ago, but I forgot to commit and push it. The commit message is also a bit confusing since I did not remember what that particular fix was good for.

Please check out the current head on the master branch on github:

https://github.com/obdev/v-usb

The pull-up or pull-down resistor on D+ is not so relevant, it should prevent stray interrupts when the computer is not connected. You can verify clock and crystal settings with a test loop, e.g.: for (;;) { toggle_port_pin(); int i; for (i = 0; i < 1000; i++) { _delay_ms(0.5); } } This should gener...

Less than 1 V when there is no traffic on the USB.

UPDATE: ... that #ifdef should resolve to TRUE, but in fact only the second macro is defined, thus preventing the correct Flash page from being read. Yes, that's a bug, the order of includes is wrong: usbportability.h is included before usbconfig.h. To fix it, simply delete the include of usbportab...

sawan sharma wrote:Is it necessary to use zener diode when i am using 9828 voltage regulator IC to make voltage 3.3v

No. You need either the zener diodes or the voltage regulator.

Thanks a lot for this great port to the ATTiny85!

We have made it possible for the application code to filter packets. See the option USB_CFG_CHECK_DATA_TOGGLING in usbconfig.h for details. This is in all versions since the October 2008 release.

No, that's not a descriptor. The table contains pre-computed CRC sum values for the CRC checksum used.

I have not looked at the code so far, but I can probably answer to questions:
(1) As far as I know, WinAVR supports C++. Simply pass it a .cpp file.
(2) The .balign 256 usbCrcTableLow: stuff is for a table-driven (and thus faster) CRC algorithm.