SH7760 Datasheet, PDF (792/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

Bit
8
7 to 0
Bit Name Initial Value R/W Description
PSM
0
R/W Power Switching Mode
This bit specifies the root hub port power switching
control method. It is implementation specific. This bit
is valid only when the NPS bit is cleared to 0.
0: All ports are powered at the same time.
1: Each port is powered individually. This mode
allows port power to be controlled by either the
global switch or per-port switching. When
HcRhDescriptorB.PPCM = H’0002, the port
responds only to port power commands
(Set/ClearPortPower). When the port mask is
cleared, then the port is controlled only by the
global power switch (Set/ClearGlobalPower).
NDP
H’02
R
Number of Downstream Ports
These bits specify the number of downstream ports
supported by the root hub. It is implementation-
specific. The value of these bits is H’2. However,
this LSI supports only 1 port for downstream.
21.3.20 Root Hub Descriptor B Register (HcRhDescriptorB)
HcRhDescriptorB is the second register of two describing the characteristics of the root hub. Set
the bits of this register on initial setup so as to cater for system implementation.
Bit: 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
PPCM
Initial value: 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R/W: R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Bit: 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
DR
Initial value: 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R/W: R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Rev. 1.0, 02/03, page 742 of 1294