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Sorry, but this is not easily possible. What you want is a USB Host, not a Device. Hosts are much more complex than Devices and can therefore not be implemented in firmware. At least not on the AVR. Look for a microcontroller with "USB To Go" hardware on chip, or combine a USB Host control...

We have released a new version of RemoteSensor: ⋅ Improved compatibility with Windows ⋅ Pull-up resistors in transmitter are now turned off when not needed. This reduces power consumption. ⋅ Fixed circuit diagram and board of receiver: USB connector pins were swapped. &...

Hi Yof,
glad to read that it works now

Can you please post more details which may be helpful for others who have similar problems? What caused the problem and how did you fix it?

RemoteSensor's receiver board up to version 2006-03-14 has an error: The USB connector is wired in reverse order (pin 1 should be pin 4, 2 should be 3 and so on). When you build the board from the schematic/board file of the project, positive an negative supply are swapped. This has undesirable effe...

As far as I can see, increasing the transfer size limit would buy us at maximum 7910 vs 6980 = 13% performance increase. I think that this is not worth the increased code size and complexity.

Reading through the code, this error probably means that HidD_GetManufacturerString() or HidD_GetProductString() failed. You can get more verbose reporting if you compile the application with -DDEBUG=1. You must start it from the command line since debug logging is done to stdout. If this is the cau...

Thanks for that information!

Can you confirm that this is due to the increased transfer size, or do you get similar results with 254 byte transfers?

This one is tricky 10: c0 01 00 00 00 00 00 04 The last two bytes here indicate a length of 0x400 = 1024 bytes. That's more than the maximum of 254 which is allowed by AVR-USB. The driver evaluates only the low byte of the length (since 254 can be expressed in one byte). And the low byte of 0x400 is...

There are two ways to force a re-enumeration after a watchdog reset: ⋅  Connect the pull-up resistor to a port pin instead of +3.3V and take this port pin low for a while during startup. The driver has provisions for this technique with the usbDeviceConnect() and usbDeviceDisconnect() macr...

The oscillator frequency must be 12 MHz +/- 0.2%. This precision is usually only met by a crystal resonator. Even a ceramic resonator may not be precise enough. The precision is computed as the number of bits in one transaction (~ 100 bits) and the maximum bit skew of 1/4 bit until the end of the tr...

Did you ensure that you recompiled the driver after defining USB_CFG_IMPLEMENT_FN_READ? Our makefiles don't have dependencies on usbconfig.h, so you must do a "make clean" after updating this header. You can verify that usbFunctionRead() is actually linked by changing the name of your func...

(This is getting off-topic -- please open a new topic for questions not directly related to the original topic.) I assume that you want to implement a control-write transfer with a non-zero data block. In order to do that, you must: ⋅  Define USB_CFG_IMPLEMENT_FN_WRITE to 1 in usbconfig.h....

The delay while pulling D+ and D- low has no effect when you first plug in the device. Since the hub or host detects the device by a high level on D- or D+ (for low or full speed respectively), the device is not detected until the delay is over. The main purpose of this type of initialization is for...

I can give you the hint to look at the fuse bits. But I'm afraid I can't help you more than that. Just have a look at the data sheet or use Atmel's AVR-Studio which represents the fuse bit meaning in clear text. You must ensure that the AVR is clocked with an external 12 MHz crystal and no additiona...

You don't need two HID descriptors, just one with a collection around two functions. I must admit that I never understood the fine details of USB descriptor parsing and always experimented until the operating system accepted the descriptor. If you can find a composite device (e.g. keyboard with trac...