protocol/pjrc/MEMO.txt

   1 Endpoint configuration
   2 ----------------------
   3 0   Control endpoint
   4 1   keyboard
   5 2   mouse
   6 3   debug
   7 4   extra key(consumer/system)
   8 5   nkro keyboard(supported only on ATmega32U4/16U4 and AT90USB64/128)
   9
  10
  11 ATmega32U4/16U4, AT90USB64/128
  12 • Endpoint 0:programmable size FIFO up to 64 bytes, default control endpoint
  13 • Endpoints 1 programmable size FIFO up to 256 bytes in ping-pong mode.
  14 • Endpoints 2 to 6: programmable size FIFO up to 64 bytes in ping-pong mode.
  15
  16 AT90USB82/162, ATmega8U2/16U2/32U2
  17 • Endpoint 0:programmable size FIFO up to 64 bytes, default control endpoint
  18 • Endpoints 1 and 2: programmable size FIFO up to 64 bytes.
  19 • Endpoints 3 and 4: programmable size FIFO up to 64 bytes with ping-pong mode.
  20
  21 ping-pong mode means double buffer feature.
  22
  23
  24 NOTE: ATmega8U2/16U2/32U2 is not supported with PJRC stack at this time.
  25 TODO: Macro definition for ATmega8U2/16U2/32U2 in usb.h