NEC switch - Manual (Page 143)

CHAPTER 8 USB FUNCTION
User’s Manual U12978EJ3V0UD
143
Figure 8-25. Flowchart of Transmit/Receive Pointer Operation (4/7)
(2) Data/Handshake packet reception (2/2)
Y
Y
Y
EOP
Y
N
N
N
N
2
1
USBPOB
overflow?
Y USBPOW
= 71H?
USBPOB increment
USBPOW increment
USBPOB increment
Idle state
Does bit stuffing
signal = 1?
Bit normal write?
EOP
received normally?
Set DBYER flag
Idle state
Set DBYER flag
Idle state
DBYER: Bit 5 of data/handshake packet receive result store register (DRXRSL)