Industrial Temperature Rated USB 2.0 Hi-Speed 2-Port Hub Controller

Datasheet

 

 

4.2.1.21

Register FBh: Port Remap 12

 

 

 

BIT

 

 

NUMBER

BIT 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 #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 4.2 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’

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’

Illegal; Do Not Use

 

to

 

 

‘1111’

 

 

 

 

SMSC USB2512Ai

23

Revision 1.97 (08-11-08)

 

DATASHEET