That will work for most usb hosts, since it breaks the specs with bulk endpoints on a low-speed dev.Then he had an idea: if the goal is only to transfer data back and forth between a computer and a microcontroller, why not write an HID-class USB serial port.While it wont work with a proper terminal such as Putty, Ray managed to whip up a serial monitor program in Processing thats compatible with Windows, Linux and OS X.Hes transferring analog values from a photoresistor as a proof of concept, but just about everything that would work with a normal serial port will work with Rays library.
HID profile is available at low speed, so he implemented serial-over-HID. Atmega8 Usb To Serial Converter Full Speed OrThe problem is that the serial port uses burst transfers, which require full speed or better. However, some operating systems happily let a low speed device use bulk transfer. Atmega8 Usb To Serial Converter Driver Signature EnforcementThe best part is that it does not require turning off Driver Signature Enforcement. They also require one to compromise security by disabling Driver Signature Enforcement in win x64. Atmega8 Usb To Serial Converter Free Virtual SerialHDDs Free Virtual Serial Port on the other hand has signed drivers for x86x64. Probably a rewrite to the Python source code to use named pipe would work. Not only do I need to buy build a programming solution, but I would need to dedicate valuable time to learning a different platform, using a different set of tools in a likely different language. Not to mention that the family come in a finer pitch (0.5 vs 0.8mm) than 1.2 ATmega8. But frankly, how much of the tiny is left for you after you put a USB stack on it Not much probably. There are bit banged serial solutions for tinys exactly for this. Its very low-cost (less than a dollar for quantity more than 100) and has hardware USB. But for many open-source projects, its still valuable to base the work on avrs and Arduino there are tons of existing libraries out there, saves a lot of time for development. Calling it serial is either redundant (all comms over USB are serial), or inaccurate (since its not recognized as a CDC serial port by the host OS). I believe tautology accusations are usually just a case of trying to be a smart arse. I solved it by checksumming all messages, ACK:ing, and storing it in flash on failure. Turned out I couldnt send a specific 8 byte long message, if sent communications would be corrupted. It just requires you also use additional descriptor string to avoid collision. I settled on two options: CP2102 modules from ebay for 2.x or FT230X or FT232R for things that need a nice PCB.
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