I/O Register Description of the HUB function
MC68HC08KH12A Data Sheet, Rev. 1.1
Freescale Semiconductor
87
EOPIE — End of Packet Detect Interrupt Enable
This read/write bit enables the USB to generate a interrupt request when the EOPF bit becomes set.
Reset clears the bit.
1 = USB interrupt enabled for End-of-Packet sequence detection
0 = USB interrupt disabled for End-of-Packet sequence detection
TRANIE — Bus Signal Transition Detect Interrupt Enable
This read/write bit enables the Signal Transition to generate a USB interrupt when the TRANF bit
becomes set. Reset clears this bit.
1 = USB interrupt enabled for Bus Signal Transition
0 = USB interrupt disabled for Bus Signal Transition
9.4.4 USB SIE Timing Status Register (SIETSR)
RSTF — USB Reset Flag
This read only bit is set when a valid reset signal state is detected on the D0+ and D0- lines. This reset
detection will also generate an internal reset signal to reset the CPU and other peripherals including
the USB module. This bit is cleared by writing a logic 1 to the RSTFR bit.
NOTE
** Please note RSTF bit is only be reset by a POR reset.
RSTFR — Clear Reset Indicator Bit
Writing a logic 1 to this write only bit will clear the RSTF bit if it is set. Writing a logic 0 to the RSTFR
has no effect. Reset clears this bit.
LOCKF — USB Frame Timer Locked
This read only bit is set when the internal frame timer is locked to the host timer. This bit is cleared by
writing a logic 1 to the LOCKFR bit. Reset clears this bit.
LOCKFR — Clear Frame Timer Locked Flag
Writing a logic 1 to this write only bit will clear the LOCKF bit if it is set. Writing a logic 0 to the LOCKFR
has no effect. Reset clears this bit.
SOFFR — Start Of Frame Flag Reset
Writing a logic 1 to this write only bit will clear the SOFF bit if it is set. Writing a logic 0 to the SOFFR
has no effect. Reset clears this bit.
EOF2FR — The Second End of Frame Point Flag Reset
Writing a logic 1 to this write only bit will clear the EOF2F bit if it is set. Writing a logic 0 to the EOF2FR
has no effect. Reset clears this bit.
Address: $0057
Bit 7
6
5
4
3
2
1
Bit 0
Read:
RSTF
0
LOCKF
0
0
0
0
0
Write:
RSTFR
LOCKFR
SOFFR
EOF2FR
EOPFR
TRANFR
Reset:
0**
0
0
0
0
0
0
0
= Unimplemented
0** = Reset by POR only
Figure 9-7. USB SIE Timing Status Register (SIETSR)