Nxp Semiconductors UM10237 User Manual
UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008
335 of 792
NXP Semiconductors
UM10237
Chapter 13: LPC24XX USB device controller
After entering the suspend state with DEV_CLK_EN and AHB_CLK_EN cleared, the
DEV_CLK_ON and AHB_CLK_ON will be cleared when the corresponding clock turns off.
When both bits are zero, USB_NEED_CLK will be low, indicating that the chip can be put
into Power-down mode by writing to the PCON register. The status of USB_NEED_CLK
can be read from the USBIntSt register.
DEV_CLK_ON and AHB_CLK_ON will be cleared when the corresponding clock turns off.
When both bits are zero, USB_NEED_CLK will be low, indicating that the chip can be put
into Power-down mode by writing to the PCON register. The status of USB_NEED_CLK
can be read from the USBIntSt register.
Any bus activity in the suspend state will cause the USB_NEED_CLK signal to be
asserted. When the USB is configured to be a wakeup source from power-down
(USBWAKE bit set in the INTWAKE register), the assertion of USB_NEED_CLK causes
the chip to wake up from Power-down mode.
asserted. When the USB is configured to be a wakeup source from power-down
(USBWAKE bit set in the INTWAKE register), the assertion of USB_NEED_CLK causes
the chip to wake up from Power-down mode.
8.4 Remote wake-up
The USB device controller supports software initiated remote wake-up. Remote wake-up
involves resume signaling on the USB bus initiated from the device. This is done by
clearing the SUS bit in the SIE Set Device Status register. Before writing into the register,
all the clocks to the device controller have to be enabled using the USBClkCtrl register.
involves resume signaling on the USB bus initiated from the device. This is done by
clearing the SUS bit in the SIE Set Device Status register. Before writing into the register,
all the clocks to the device controller have to be enabled using the USBClkCtrl register.
9.
Register description
The Serial Interface Engine (SIE) has other registers that are indirectly accessible via the
SIE command registers. See
SIE command registers. See
for more info.
Table 293. Summary of USB device registers
Name
Description
Access
Reset value
Address
Port select register
USBPortSel
USB Port Select
R/W
0x0000 0000
0xFFE0 C110
Clock control registers
USBClkCtrl
USB Clock Control
R/W
0x0000 0000
0xFFE0 CFF4
USBClkSt
USB Clock Status
RO
0x0000 0000
0xFFE0 CFF8
Device interrupt registers
USBIntSt
USB Interrupt Status
R/W
0x8000 0000
0xE01F C1C0
USBDevIntSt
USB Device Interrupt Status
RO
0x0000 0010
0xFFE0 C200
USBDevIntEn
USB Device Interrupt Enable
R/W
0x0000 0000
0xFFE0 C204
USBDevIntClr
USB Device Interrupt Clear
WO
0x0000 0000
0xFFE0 C208
USBDevIntSet
USB Device Interrupt Set
WO
0x0000 0000
0xFFE0 C20C
USBDevIntPri
USB Device Interrupt Priority
WO
0x00
0xFFE0 C22C
Endpoint interrupt registers
USBEpIntSt
USB Endpoint Interrupt Status
RO
0x0000 0000
0xFFE0 C230
USBEpIntEn
USB Endpoint Interrupt Enable
R/W
0x0000 0000
0xFFE0 C234
USBEpIntClr
USB Endpoint Interrupt Clear
WO
0x0000 0000
0xFFE0 C238
USBEpIntSet
USB Endpoint Interrupt Set
WO
0x0000 0000
0xFFE0 C23C
USBEpIntPri
USB Endpoint Priority
0x0000 0000
0xFFE0 C240
Endpoint realization registers
USBReEp
USB Realize Endpoint
R/W
0x0000 0003
0xFFE0 C244