Restriction and Bug
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Not statble yet.
+
+Can't bus-reset a keyboard which already attached on bus properly.
+ Slow start up of Leonardo's bootloader causes this?
+ Need to unplug/plug a keyboard after firmware starts up.
+ MAX3421E doesn't work SAMPLEBUS well to know whether device connected or not.
+
+Keyboard with other endpoints than boot keyboard may go wrong.
+ On my keyboard with mouse key the converter locks up when using mouse key function.