NEC switch - Format of Packet Receive Status Register

CHAPTER 8 USB FUNCTION
User’s Manual U12978EJ3V0UD
112
Figure 8-12. Format of Packet Receive Status Register
Symbol 67 543210
UWDERR RESMRX SE0RX URESRX EOPRX HSSTAT DASTAT TOSTAT
UWDERR USB timer inadvertent program loop detection
0
1
FF67H
Address
RXSTAT
After reset
00H
R/W
R/W
No USB timer inadvertent program loop was detected.
USB timer inadvertent program loop (USB clock operation faster than 85.3 s (at 6.0 MHz)) was detected,
forcibly terminating USB clock. This flag is also set when USB reset or Resume signal was received.
RESMRX Resume signal receive status
0
1
No Resume signal was received.
Received Resume signal (level detection)
SE0RX Single-ended 0 signal detection status
0
1
No Single-ended 0 (SE0) signal was detected.
Detected SE0 signal one or more times
URESRX USB reset signal detection status
0
1
No USB reset signal was detected.
Detected USB reset signal one or more times
EOPRX EOP detection status
0
1
No EOP signal was detected.
Detected EOP one or more times
HSSTAT Handshake packet receive status
0
1
No handshake packet was received.
Receiving handshake packet
DASTAT Data packet receive status
0
1
No data packet was received.
Receiving data packet
TOSTAT Token packet receive status
0
1
No token packet was received.
Receiving token packet
Note
µ
Note Bits 0 to 2: read only