Datasheet

USB251xB/xBi
DS00001692C-page 24  2010 - 2015 Microchip Technology Inc.
5.1.10 REGISTER 09H: NON-REMOVABLE DEVICE
5.1.11 REGISTER 0AH: PORT DISABLE FOR SELF-POWERED OPERATION
Bit Number Bit Name Description
7:0 NR_DEVICE Non-Removable Device: indicates which port has a non-removable device.
0 : port is removable
1 : port is non-removable
Bit 7 : rsvd
Bit 6 : rsvd
Bit 5 : rsvd
Bit 4 : controls port 4
Bit 3 : controls port 3
Bit 2 : controls port 2
Bit 1 : controls port 1
Bit 0 : rsvd
Note: The device must provide its own descriptor data.
When using the default configuration, the NON_REM[1:0] pins will designate
the appropriate ports as being non-removable.
Bit Number Bit Name Description
7:0 PORT_DIS_SP Port Disable Self-Powered: disables one or more ports.
0 = port is available
1 = port is disabled
Bit 7 : rsvd
Bit 6 : rsvd
Bit 5 : rsvd
Bit 4 : controls port 4
Bit 3 : controls port 3
Bit 2 : controls port 2
Bit 1 : controls port 1
Bit 0 : rsvd
During self-powered operation when mapping mode is disabled (
PRTMAP_EN
= 0), this register selects the ports that will be permanently disabled. These
ports are then unavailable and cannot be enabled or enumerated by a host
controller. The ports can be disabled in any order, where the internal logic will
automatically report the correct number of enabled ports to the USB host. The
active ports will be reordered in order to ensure proper function.
When using the default configuration, PRT_DIS_P[x:1] and PRT_DIS_M[x:1]
pins disable the appropriate ports.