NEC switch - Manual (Page 141)

CHAPTER 8 USB FUNCTION
User’s Manual U12978EJ3V0UD
141
Figure 8-25. Flowchart of Transmit/Receive Pointer Operation (2/7)
(1) Token packet reception (2/2)
Y
Y
Y
EOP
Y
N
N
N
2
USBPOW
= 05H?
USBPOB increment
Idle state
Does bit stuffing
signal = 1?
Bit normal write?
EOP
normal receive?
Set TBYER flag
Idle state
Set TBYER flag
Idle state
TBYER: Bit 5 of token packet receive result store register (TRXRSL)