Datasheet

Universal Serial Bus Module (USB)
I/O Registers
MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3 Technical Data
Freescale Semiconductor Universal Serial Bus Module (USB) 153
9.8.11 USB Status Register 1
R2SEQ — Endpoint 2 Receive Sequence Bit
This read-only bit indicates the type of data packet last received for
endpoint 2 (DATA0 or DATA1).
1 = DATA1 token received in last endpoint 2 receive
0 = DATA0 token received in last endpoint 2 receive
TXACK — ACK Token Transmit Bit
This read-only bit indicates that an ACK token has been transmitted.
This bit is updated at the end of the EP0 data transmission.
1 = Last token transmitted for endpoint 0 was an ACK token
0 = Last token transmitted for endpoint 0 was not an ACK token
TXNAK — NAK Token Transmit Bit
This read-only bit indicates that a TXNAK token has been transmitted.
This bit is updated at the end of the EP0 data transmission.
1 = Last token transmitted for endpoint 0 was a NAK token
0 = Last token transmitted for endpoint 0 was not a NAK token
TXSTL — STALL Token Transmit Bit
This read-only bit indicates that a STALL token has been transmitted.
This bit is updated at the end of the EP0 data transmission.
1 = Last token transmitted for endpoint 0 was a STALL token
0 = Last token transmitted for endpoint 0 was not a STALL token
RP2SIZ3–RP2SIZ0 — Endpoint 2 Receive Data Packet Size
These read-only bits store the number of data bytes received for the
last OUT transaction for endpoint 2.
Address: $003E
Bit 7654321Bit 0
Read:
R2SEQ TXACK TXNAK TXSTL RP2SIZ3 RP2SIZ2 RP2SIZ1 RP2SIZ0
Write:
Reset:U0 0 0UUUU
= Unimplemented U = Unaffected by reset
Figure 9-25. USB Status Register 1 (USR1)