Nxp Semiconductors UM10237 ユーザーズマニュアル
UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008
411 of 792
NXP Semiconductors
UM10237
Chapter 15: LPC24XX USB OTG controller
8.1 B-device: peripheral to host switching
In this case, the default role of the OTG controller is peripheral (B-device), and it switches
roles from Peripheral to Host.
roles from Peripheral to Host.
The On-The-Go Supplement defines the behavior of a dual-role B-device during HNP
using a state machine diagram. The OTG software stack is responsible for implementing
all of the states in the Dual-Role B-Device State Diagram.
using a state machine diagram. The OTG software stack is responsible for implementing
all of the states in the Dual-Role B-Device State Diagram.
The OTG controller hardware provides support for the state transitions between the states
b_peripheral, b_wait_acon, and b_host in the Dual-Role B-Device state diagram. Setting
B_HNP_TRACK in the OTGStCtrl register enables hardware support for the B-device
switching from peripheral to host. The hardware actions after setting this bit are shown in
b_peripheral, b_wait_acon, and b_host in the Dual-Role B-Device state diagram. Setting
B_HNP_TRACK in the OTGStCtrl register enables hardware support for the B-device
switching from peripheral to host. The hardware actions after setting this bit are shown in
Fig 59. USB OTG controller with software stack
HOST
CONTROLLER
MUX
OHCI
STACK
OTG
STACK
DEVICE
STACK
USB BUS
ISP1301
OTG
CONTROLLER
DEVICE
CONTROLLER
I2C
CONTROLLER