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High-Speed USB Host Subsystem
Table 22-49. Serial Mode Description, Signal Functionality
Usual Name
6-Pin
6-Pin
3-Pin
4-Pin
6-Pin
6-Pin
3-Pin
4-Pin
2-Pin
2-Pin
Mode
Mode
Mode
Mode
TLL
TLL
TLL
TLL
TLL
TLL
(Alt)
Mode
(Alt)
Mode
Mode
Mode
(Alt)
Mode
Mode
USBHOST.
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
0xA
0xB
:24] FSLSMODE
field
TX encoding
DAT/SE0
DP/DM
DAT/SE0
DP/DM
DAT/SE
DP/DM
DAT/SE
DP/DM
DAT/SE
DP/DM
0
0
0
RX encoding
DP/DM/R
DP/DM/
DAT/SE0
DP/DM/
DP/DM/
DP/DM/
DAT/SE
DP/DM/
DAT/SE
DP/DM
CV
RCV
RCV
RCV
RCV
0
RCV
0
Pin usage
Unidirecti
Unidirect Bidirection Bidirecti
Unidirect Unidirect Bidirecti
Bidirecti
Bidirecti
Bidirecti
onal
ional
al
onal
ional
ional
onal
onal
onal
onal
Pin count
6
6
3
4
6 or 5
(1)
6 or 5
(1)
3
4 or 3
(2)
2
2
I/O Pad Function Per Mode
TXEN
TX Enable TX
TX Enable TX
TX
TX
TX
TX
N/C
N/C
Enable
Enable
Enable
Enable
Enable
Enable
TXDAT
TX Diff
TX SE
TX/RX
TX/RX
TX Diff
TX SE
TX/RX
TX/RX
TX/RX
TX/RX
Data
Plus
Diff Data
SE Plus
Data
Plus
Diff Data
Diff Data
Diff Data SE Plus
Data
Data
Data
Data
TXSE0
TX force
TX SE
TX/RX
TX/RX
TX force
TX SE
TX/RX
TX/RX
TX/RX
TX/RX
SE0
Minus
force SE0
SE
SE0
Minus
force
force
force
SE
Data
Minus
Data
SE0
SE0
SE0
Minus
Data
Data
RXRCV
RX Diff
RX Diff
N/C
RX Diff
RX Diff
RX Diff
N/C
RX Diff
N/C
N/C
Data
Data
Data
Data
Data
Data
RXDM
RX SE
RX SE
N/C
N/C
RX SE
RX SE
N/C
N/C
N/C
N/C
Plus Data
Plus
Plus
Plus
Data
Data
Data
RXDM
RX SE
RX SE
N/C
N/C
RX SE
RX SE
N/C
N/C
N/C
N/C
Minus
Minus
Minus
Minus
Data
Data
Data
Data
(1)
RXRCV and RXDM carry the same info: RXDM can drive both inputs of the remote controller and RXRCV kept unused
(2)
Same remark on TXDAT (for outputs) and RXRCV: TXDAT only is enough
22.2.4.2.6 Attach/Connect Emulation for Serial TLL Modes
This section applies to all serial TLL modes:
•
In UTMI-to-serial mode (USBHOST.
[2:1] CHANMODE field = 0x1) for all TLL
values of USBHOST.
[27:24] FSLSMODE field (0x4 to 0x7; 0xA to 0xB)
•
In UTMI-to-ULPI TLL mode (USBHOST.
[2:1] CHANMODE field = 0x0) when
the ULPI bus is switched to 6-pin serial or 3-pin serial modes
In those modes, the USB bus lines are emulated by USBTLL internal logic, and are never available on the
outside. The pullup/pulldown actions described in the USB specification cannot be applied directly, and the
USB cable cannot be physically attached.
Because serial modes do not specify a standard format for those sideband settings, a custom
software-controlled one was implemented:
•
[4] TLLATTACH bit emulates the physical attachment of the two
controllers through a TLL cable.
–
When this bit is cleared, the local controller RX path only shows the local controller (the high-speed
USB host controller) actions on the bus: TX driving, pullups, pulldowns (see below). The same thing
applies for the remote controller RX path (except that test override is not available).
–
As soon as the bit is set, the actions of both sides are applied to the same bus and are resolved,
similar to a real bus. The RX path for both sides shows the same bus state.
•
[5] TLLCONNECT bit emulates the USB electrical connect (that is,
the pullup by the USB peripheral of one of the two USB lines [by a 1.5KOhm resistor]), which causes
3279
SWPU177N – December 2009 – Revised November 2010
High-Speed USB Host Subsystem and High-Speed USB OTG Controller
Copyright © 2009–2010, Texas Instruments Incorporated