Datasheet

32.8.7.4 Extended Register
Name: EXTREG
Offset: 0x08
Reset: 0xxxxxxxx
Property: NA
Bit 15 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
Bit 7 6 5 4 3 2 1 0
VARIABLE[3:0] SUBPID[3:0]
Access
R/W R/W R/W R/W R/W R/W R/W R/W
Reset 0 0 0 x 0 0 0 x
Bits 14:4 – VARIABLE[10:0] Variable field send with extended token
These bits define the VARIABLE field sent with extended token. 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 set as described
below.
VARIABLE Description
VARIABLE[3:0] bLinkState
(1)
VARIABLE[7:4] BESL (See LPM ECN)
(2)
VARIABLE[8] bRemoteWake
(1)
VARIABLE[10:9] Reserved
(1) 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"
(2) 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
These bits define the SUBPID field sent with extended token. 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 SUBPID field should be set as described in
“Table 2.2 SubPID Types in the reference document ENGINEERING CHANGE NOTICE, USB 2.0 Link
Power Management Addendum”.
SAM D21 Family
USB – Universal Serial Bus
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40001882D-page 886