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Does anyone know what the actual baud rate that the CDC Based virtual serial port on the Leonardo runs at is? Serial::being() for the CDC version is just empty, so it's not setting a baud rate anywhere.

Basically, I'm debating between using the 32u4 or the 328p with an FTDI chip and trying to figure out if the 32u4 will be slower... since it uses a virtual COM port I'm assuming it is, but I'd be happy if I was wrong :)

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I'm not sure if the concept of an "actual baud rate" is really meaningful in a pure USB connection.

In my experience, the 32u4 is faster than the 328p at serial-heavy tasks. There is no intermediate chip, and USB has much larger hardware buffers than the serial port does. I don't know how much processing you're planning to do on your data, but I would expect that a 32u4 can process serial data pretty much as fast as you can generate/process it.

On the host side, it seems to me that there is very little difference in whether the "virtual COM port" has an FTDI or a 32u4 on the other end, so I don't see why one should be faster than the other (though admittedly they go through different device drivers).

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