Filter
Top Products
www.digiembedded.com
753
USB Controller Module
HcRhDescriptorA register
Address: 9010 1048
The HcRhDescriptorA register is the first of two registers describing the
characteristics of the root hub. The root hub is the logical hub built into a USB host.
Reset values are implementation-specific.
Register bit assignment
Bits Access Mnemonic Reset Description
D31:24 R/W POTPGT IS PowerOnToPowerGoodTime
Specifies the length of time the host controller driver has
to wait before accessing a powered-on port of the root hub.
The unit of time is 2 ms. The duration is calculated as
POTPGT*2 ms.
D23:13 N/A Reserved N/A N/A
D12 R/W NOCP IS NoOverCurrentProtection
Describes how the overcurrent status for the root hub ports
is reported. When the NOCP bit is cleared, the
OverCurrentProtectionMode field (D11 in this register)
specifies global or per-port reporting:
0 Overcurrent status is reported collectively for all
downstream ports.
1 No overcurrent protection supported.
Table 441: HcRhDescriptorA register
NDP
13121110987654321015 14
31 29 28 27 26 25 24 23 22 21 20 19 18 17 1630
POTPGT
Reserved
Reserved
NOCP OCPM DT PSM NPS