Objective Development Forums

It is possible and I have seen code which shares the USB driver between boot loader and main code. Can't remember the reference, though. However, in general, I'd really recommend against this solution. That's because most of V-USB's features are compile time constants. You would have to ensure that ...

Did you have a look at Osamu Tamura's pages at http://www.recursion.jp/avrcdc/

He has a similar problem with CDC (which requires bulk endoints) on Windows 7 and as far as I know, he came up with a patch.

I originally thought that we can use 5V levels, although it does not meet the specs. It turned out, though, that (at that time) newer USB host chips did not cope with those high levels. Similarly the bulk endpoints: When the feature was implemented, all operating systems accepted them for low speed ...

From the USB specification (this is from version 1.1): 7.1.6 Input Characteristics The input impedance of D+ or D- without termination should be > 300 kOhm (ZINP). The input capacitance of a port is measured at the connector pins. [...] You clearly don't meet this part of the spec. On the other hand...

Thanks for your project publication! When you have published a new project, please drop us a note via

http://www.obdev.at/vusb/feedback.html

as we don't always monitor the forums.

Your questions are too general to be answered in a forum posting. The hardware connections are certainly OK. However, we can't write the firmware for you. If you have a specific problem with the descriptor, with key up/down handling or similar, we may be able to help.

usbConnect() and usbDisconnect() are emulated when no pull-up pin is defined. That's OK. Then, let me summarize: You can run any of the example apps on the board, but none of the boot loaders, even if you load them as app (not into boot space). That's rather strange, because the driver is the same i...

Yes, it's code plus data, so it should fit. If it still fails when flashed to 0 with TEST_MODE defined, you can try to debug it with debug output on TxD. There is no code size limit when you flash it to address 0.

On the other hand: Have you tried other bootloaders, e.g. USBaspLoader?

The define in bootloadHID is "TEST_MODE". Did you check the over-all code size? It might exceed the 2k of the boot area.

You can first try to load it as normal application at address 0 instead of the boot area. Don't know which boot loader you use, but USBaspLoader has an optional define "NO_FLASH_WRITE". If you set it, it's compiled as normal application which can be loaded at address 0.

You don't need to change anything here, the code you quote already takes care of the p suffix devices.

BTW: The "$" does not mean words or bytes here, it means that the value is in hex, not in dec.

You want

Boot Flash size=1024 words start address=$3C00

That's 2048 BYTES of boot flash size starting at the correct position.

No. Half of 7800 is 3C00. And you should choose a boot section size of 1024 words (= 2048 bytes).

The figures from AVR Studio are in words (16 bits = 2 bytes) while gcc's values and thus the values specified in the Makefile are in bytes.

Thanks for pointing this out! Yes, it IS a bug. Please report such bugs via http://www.obdev.at/vusb/feedback.html, since we don't read the forums regularly.