UPSD3422_06 Datasheet, PDF (159/293 Pages) STMicroelectronics – Turbo Plus Series Fast Turbo 8032 MCU with USB and Programmable Logic

uPSD34xx
USB interface
● USB Global Interrupt Flag Register (UIF0)
There are many different events that generate a USB interrupt requiring a number of
registers to indicate the cause of the interrupt. To more efficiently identify the cause of
the interrupt, the USB Global Interrupt Flag Register (see Table 76) indicates the type
of interrupt that occurred. Once the type of interrupt is identified, the associated
Interrupt Flag Register may be read to determine the exact cause of the interrupt.
Table 76.
Bit 7
GLF
USB global interrupt flag register (UIF0 0E8h, reset value 00h)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
INF
OUTF
NAKF
RSTF SUSPENDF EOPF RESUMF
Bit
Symbol
R/W
Definition
Global Interrupt flag
7
GLF
R _{Logical OR of the RSTF, SUSPENDF, EOPF, and RESUMF}
interrupt flags
IN FIFO Interrupt flag
6
INF
R _{Logical OR of the IN4F, IN3F, IN2F, IN1F, and IN0F interrupt}
flags
OUT FIFO Interrupt flag
5
OUTF
R _{Logical OR of the OUT4F, OUT3F, OUT2F, OUT1F, and OUT0F}
interrupt flags
NAK FIFO Interrupt flag
4
NAKF
R Logical OR of the NAK4F, NAK3F, NAK2F, NAK1F, and NAK0F
interrupt flags
USB Reset flag
This bit is set when a USB Reset is detected on the D+ and D-
lines.
3
RSTF
R/W _{Note: A USB Reset does not reset the MCU nor the USB}
module. Firmware should disable/enable the USB SIE using
the USEN bit in the UCTL register and initialize all USB related
registers as appropriate.
USB suspend mode flag
2
SUSPENDF R/W ^{This bit is set when the SIE detects 3ms of no activity on the}
bus and the clock to the SIE is also shut down to conserve
power. Clearing this bit turns the SIE clock on.
End of Packet flag
1
EOPF
R/W This bit is set when a valid End of Packet sequence is detected
on the D+ and D– line.
Resume flag
0
RESUMEF R/W ^{This bit is set when USB bus activity is detected while the}
SUSPNDF Bit is set. When a Resume is detected, the
SUSPENDF bit must be cleared (if set) to turn the SIE clock on.
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