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Table 64. OTG System Configuration Register 2 (OTG_SYSCON_2) (Continued)
Bit
Name
22:20
A_WAIT_VRISE
19
Reserved
18:16
B_ASE0_BRST
15
Reserved
† See Table 65, OTG_PADEN Source Status.
‡ See Table 66, HMC_PADEN: USB Signal Multiplexing Control Source.
SPRU761A
Description
Offset for A_WAIT_VRISE timer.These bits define the maximum duration
that the OTG controller must wait for VBUS to rise above the A-device
VBUS valid threshold. A_WAIT_VRISE is used only when OMAP5912 acts
as a default-A device. The A_WAIT_VRISE counter begins counting upon
transition from the A_IDLE state. (See the On-The-Go Supplement to the
USB 2.0 Specification Revision 1.0 description of the dual-role A-device
state diagram).
0x0: Maximum delay in A_WAIT_VRISE state is 200 ms nominal.
0x1: Maximum delay in A_WAIT_VRISE state is 287.04 ms nominal.
0x2: Maximum delay in A_WAIT_VRISE state is 374.08 ms nominal.
0x3: Maximum delay in A_WAIT_VRISE state is 548.16 ms nominal.
This register is cleared 0x0 by soft reset or hardware reset.
If the A_WAIT_VRISE counter expires before VBUS rises above the
A-device VBUS valid threshold, it indicates that there is a heavy load on
VBUS. The OTG controller state machine transitions to A_VBUS_ERR and
generates a VBUS error interrupt.
Reserved
Offset for B_ASE0_BRST timer. These bits control how the USB OTG
controller manages disabling the D+ pullup when acting as a default-B
OTG dual-role device and transitioning from state b_peripheral to
b_wait_acon, and when acting as a default-A OTG dual-role device and
transitioning from state a_peripheral to a_wait_bcon. The setting of this
register controls the mechanism by which the OMAP5912 OTG controller
knows that the D+ pullup is disabled.
Because OMAP5912 implementations control the D+ pullup using an I
link to an OTG transceiver, the only allowed setting is 0x4. When in this
mode of operation, system software must write a 1 to
OTG_CTRL.OTG_PU immediately after completion of the I
that disables the D+ pullup.
This field is cleared 0x0 by soft reset or hardware reset. This field has no
effect when OTG is disabled. This field must not be changed when OTG
functionality is enabled (OTG_SYSCON_2.OTG_EN=1).
Reserved
USB OTG Controller
2
C operation
Universal Serial Bus (USB)
2
C
205
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