Ultra Fast USB 2.0 Multi-Format Flash Media Controller/USB Hub Combo

7.3.3.31F2h: Port Remap 12

BIT

 

 

NUMBER

BYTE NAME

DESCRIPTION

 

 

 

7:0

PRTR12

Port remap register for ports 1 & 2.

 

 

When a hub is enumerated by a USB Host Controller, the hub is only

 

 

permitted to report how many ports it has; the hub is not permitted to select

 

 

a numerical range or assignment. The Host Controller will number the

 

 

downstream ports of the hub starting with the number '1', up to the number

 

 

of ports that the hub reported having.

 

 

The host's port number is referred to as "Logical Port Number" and the

 

 

physical port on the hub is the “Physical Port Number". When remapping

 

 

mode is enabled (see PRTMAP_EN in Register 08h: Configuration Data

 

 

Byte 3) the hub's downstream port numbers can be remapped to different

 

 

logical port numbers (assigned by the host).

 

 

Note: OEM must ensure that Contiguous Logical Port Numbers are used,

 

 

starting from number ‘1’ up to the maximum number of enabled

 

 

ports; this ensures that the hub's ports are numbered in accordance

 

 

with the way a host will communicate with the ports.

Table 7.5 Port Remap Register for Ports 1 & 2

Bit [7:4]

‘0000’

Physical Port 2 is Disabled

 

 

 

 

‘0001’

Physical Port 2 is mapped to Logical Port 1

 

 

 

 

‘0010’

Physical Port 2 is mapped to Logical Port 2

 

 

 

 

‘0011’

Physical Port 2 is mapped to Logical Port 3

 

 

 

 

‘0100’

Illegal; Do Not Use

 

to

 

 

‘1111’

 

 

 

 

Bit [3:0]

‘0000’

Physical Port 1 is Disabled

 

 

 

 

‘0001’

Physical Port 1 is mapped to Logical Port 1

 

 

 

 

‘0010’

Physical Port 1 is mapped to Logical Port 2

 

 

 

 

‘0011’

Physical Port 1 is mapped to Logical Port 3

 

 

 

 

‘0100’

Illegal; Do Not Use

 

to

 

 

‘1111’

 

 

 

 

SMSC USB2640/USB2641

45

Revision 2.0 (10-03-08)

 

DATASHEET