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SH7727 Datasheet, PDF (821/1109 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7700 Series
Section 24 USB HOST Module
24.2.20 HcRhDescriptorB
HcRhDescriptorB Register (H'0400044C)
The HcRhDescriptorB register is the second register of two registers describing the features of the
root hub. These bits are written during the initial setting so as to correspond to the system
implementation. The reset value is implementation specific.
Register: HcRhDescriptorB
Bits
Reset R/W
31–16 0h
R/W
15–0
0h
R/W
Offset: 4C–4F
Description
PortPowerControlMask (PPCM)
This bit indicates that the port is influenced by the global power-
control command when the PowerSwitchingMode bit is set.
When this bit is set, the power state of the port is affected by
the power control at each port (set/clear port power). When this
bit is cleared, the port is controlled by the global power switch
(set/clear global power). If the device is placed in the global
switching mode (PowerSwitchingMode = 0), this bit is not valid.
Bit 15: Assured
Bit 16: Port#1 power mask
Bit 17: Port#2 power mask
…
Bit 31: Port#15 power mask
Note: Clear the No Power Switching of the RhDescriptorA
register so that the power to all ports is OFF (Port
Power Status = 0), then set this bit.
DeviceRemoveable (DR)
These bits are dedicated to the ports of the root hub. When
these bits are cleared, the set device becomes removable.
When these bits are set, do not remove the set device.
Bit 0: Assured
Bit 1: Device affixed to Port#1
Bit 2: Device affixed to Port#2
…
Bit 15: Device affixed to Port#15
Rev. 5.00 Dec 12, 2005 page 749 of 1034
REJ09B0254-0500