28 USB FUNCTION CONTROLLER (USB)
28-36
Seiko Epson Corporation
S1C33L26 TECHNICAL MANUAL
D7
VBUS
This bit displays the status of the USBVBUS pin.
D6
FS
Returns always 1 (FS mode).
D[5:2]
Reserved
D[1:0]
LineState[1:0]
Shows the signal status on the USB cable.
Shows the value received by the FS receiver of the DP/DM.
LineState
LineState[1:0]
DP/DM
0x3
SE1
0x2
K
0x1
J
0x0
SE0
XcvrControl (Xcvr Control)
Register name Address
Bit
Name
Setting
Init. R/W
Remarks
XcvrControl
(Xcvr control)
0x300c23
(8 bits)
D7
RpuEnb
1 Enable pull-up
0 Disable pull-up
0
R/W
D6–2 –
–
–
–
0 when being read.
D1–0 OpMode[1:0]
OpMode[1:0]
Operation mode
0x1 R/W
0x3
0x2
0x1
0x0
reserved
Disable bitstuffing and NRZI encoding
Non-driving
Normal operation
The operation setting is done for the Transceiver macro.
D7
RpuEnb
This bit enables the D+ pull-up resistor.
D[6:2]
Reserved
D[1:0]
OpMode
This bit sets the operation mode of the Transceiver macro.
This bit needs not be set up normally, excluding when the USB cable is pulled off (*) and during the
test mode.
OpMode
OpMode[1:0]
Operation mode
0x3
Reserved
0x2
Disable bitstuffing and NRZI encoding
0x1
Non-driving
0x0
Normal operation
* When the USB cable is pulled off, it is recommended to set this register to 0x1.
USB_Test (USB Test)
Register name Address
Bit
Name
Setting
Init. R/W
Remarks
USB_Test
(USB test)
0x300c24
(8 bits)
D7
EnUSB_Test
1 Enable USB test
0 Do nothing
0
R/W
D6–4 –
–
–
–
0 when being read.
D3
Test_SE0_NAK
1 Test_SE0_NAK
0 Do nothing
0
R/W
D2
Test_J
1 Test_J
0 Do nothing
0
R/W
D1
Test_K
1 Test_K
0 Do nothing
0
R/W
D0
Test_Packet
1 Test_Packet
0 Do nothing
0
R/W
The operation setting is done in this register for the USB test mode. Set the bit corresponding to the test mode
specified by the SetFeature request, and after completing the status stage, set the EnUSB_Test bit to 1 and perform
the test mode operation defined by the USB standard.