USB Registers
Table 16-110. USB1CTRL Register Field Descriptions (continued)
Bit
Field
Type
Reset
Description
0
SOFT_RESET
R/W
0h
Software reset of USB1.
Write 0 = no action
Write 1 = Initiate software reset
Read 0 = Reset done, no action
Read 1 = Reset ongoing
Both the soft_reset and soft_reset_isolation bits should be asserted
simultaneously.
This will cause the following sequence of actions to occur over
multiple cycles:
- All USB0 output signals will go to a known constant value via
multiplexers.
This removes the possibility of timing errors due to the asynchronous
resets.
- All USB0 registers will be reset.
- The USB0 resets will be de-asserted.
- The reset isolation multiplexer inputs will be de-selected.
- Both the soft_reset and soft_reset_isolation bits will be
automatically cleared.
Setting only the soft_reset_isolation bit will cause all USB0 output
signals to go to a known constant value via multiplexers.
This will prevent future access to USB0.
To clear this condition the USBSS must be reset via a hard or soft
reset.
1857
SPRUH73H – October 2011 – Revised April 2013
Universal Serial Bus (USB)
Copyright © 2011–2013, Texas Instruments Incorporated