MCBSTM32EXL Keil, MCBSTM32EXL Datasheet - Page 831

• Manufacturer Part Number: MCBSTM32EXL
• Description: BOARD EVALUATION FOR STM32F103ZE
• Manufacturer: Keil

Specifications of MCBSTM32EXL

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

RM0008
Figure 280. A-Device SRP
1. DRV_VBUS = V
1.
2.
3.
4.
5.
6.
7.
B-device session request protocol
The application must set the SRP-capable bit in the Core USB configuration register. This
enables the OTG_FS controller to initiate SRP as a B-device. SRP is a means by which the
OTG_FS controller can request a new session from the host.
VBUS_VALID = V
A_VALID = A-peripheral V
D+ = Data plus line
D- = Data minus line
To save power, the application suspends and turns off port power when the bus is idle
by writing the port suspend and port power bits in the Host port control and status
register.
PHY indicates port power off by deasserting the VBUS_VALID signal.
The device must detect SE0 for at least 2 ms to start SRP when V
To initiate SRP, the device turns on its data line pull-up resistor for 5 to 10 ms. The
OTG_FS controller detects data-line pulsing.
The device drives V
pulsing.
The OTG_FS controller interrupts the application on detecting SRP. The Session
request detected bit is set in Global interrupt status register (SRQINT set in
OTG_FS_GINTSTS).
The application must service the Session request detected interrupt and turn on the
port power bit by writing the port power bit in the Host port control and status register.
The PHY indicates port power-on by asserting the VBUS_VALID signal.
When the USB is powered, the device connects, completing the SRP process.
DRV_VBUS
VBUS_VALID
A_VALID
D+
D-
BUS
BUS
Suspend
Low
drive signal to the PHY
valid signal from PHY
BUS
BUS
1
level signal to PHY
above the A-device session valid (2.0 V minimum) for V
2
Doc ID 13902 Rev 9
3
4
Data line pulsing
USB on-the-go full-speed (OTG_FS)
V
BUS
6
5
pulsing
BUS
7
power is off.
Connect
ai15681
831/995
BUS