EXTREG

Name:: EXTREG
Offset:: 0x08
Reset:: 0xxxxxxxx
Access:: NA

Bit15	14	13	12	11	10	9	8
	VARIABLE[10:4]
Access	R/W	R/W	R/W	R/W	R/W	R/W	R/W
Reset	0	0	0	0	0	0	0
Bit7	6	5	4	3	2	1	0
VARIABLE[3:0]				SUBPID[3:0]
AccessR/W	R/W	R/W	R/W	R/W	R/W	R/W	R/W
Reset0	0	0	0	0	0	0	0

Bits 14:4 – VARIABLE[10:0]: Variable field send with extended token

Variable field send with extended token

These bits define the VARIABLE field of a received extended token. These bits are updated when the USB has answered by an handshake token ACK to a LPM transaction. See Section 2.1.1 Protocol Extension Token in the reference document “ENGINEERING CHANGE NOTICE, USB 2.0 Link Power Management Addendum”.

To support the USB2.0 Link Power Management addition the VARIABLE field should be read as described below.

VARIABLES	Description
VARIABLE[3:0]	bLinkState (1)
VARIABLE[7:4]	BESL (2)
VARIABLE[8]	bRemoteWake (1)
VARIABLE[10:9]	Reserved

For a definition of LPM Token bRemoteWake and bLinkState fields, refer to "Table 2-3 in the reference document ENGINEERING CHANGE NOTICE, USB 2.0 Link Power Management Addendum".
For a definition of LPM Token BESL field, refer to "Table 2-3 in the reference document ENGINEERING CHANGE NOTICE, USB 2.0 Link Power Management Addendum" and "Table X-X1 in Errata for ECN USB 2.0 Link Power Management.

Bits 3:0 – SUBPID[3:0]: SUBPID field send with extended token

SUBPID field send with extended token

These bits define the SUBPID field of a received extended token. These bits are updated when the USB has answered by an handshake token ACK to a LPM transaction. See Section 2.1.1 Protocol Extension Token in the reference document “ENGINEERING CHANGE NOTICE, USB 2.0 Link Power Management Addendum”.