USB : USB Classes USB Classes for Microcontrollers |
What's going on here? The CDC device driver is constantly requesting data from the device, hundreds of times in every 1 msec USB frame, that's what. It's a (useless) conversation like this:
"Do you have anything for me?"
"No.""How about now?"
"Nope.""Now?"
"Not yet."
...and on and on, over and over, burning up 50% of the full speed USB bus bandwidth.
What a waste! All that bandwidth gone, just to give you something that's no smarter than an old time serial port!
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