TM4C1233C3PM Datasheet, PDF (337/1214 Pages) Texas Instruments – Tiva Microcontroller

Tiva^™ TM4C1233C3PM Microcontroller
Register 64: Universal Serial Bus Run Mode Clock Gating Control (RCGCUSB),
offset 0x628
The RCGCUSB register provides software the capability to enable and disable the USB module in
Run mode. When enabled, the module is provided a clock and accesses to module registers are
allowed. When disabled, the clock is disabled to save power and accesses to module registers
generate a bus fault. This register provides the same capability as the legacy Run Mode Clock
Gating Control Register n RCGCn registers specifically for the watchdog modules and has the
same bit polarity as the corresponding RCGCn bits.
Important: This register should be used to control the clocking for the USB module. To support
legacy software, the RCGC2 register is available. A write to the USB0 bit in the RCGC2
register also writes the R0 bit in this register. If the USB0 bit is changed by writing to the
RCGC2 register, it can be read back correctly with a read of the RCGC2 register. If
software uses this register to control the clock for the USB module, the write causes
proper operation, but the USB0 bit in the RCGC2 register does not reflect the value of
the R0 bit. If software uses both legacy and peripheral-specific register accesses, the
peripheral-specific registers must be accessed by read-modify-write operations that
affect only peripherals that are not present in the legacy registers. In this manner, both
the peripheral-specific and legacy registers have coherent information.
Universal Serial Bus Run Mode Clock Gating Control (RCGCUSB)
Base 0x400F.E000
Offset 0x628
Type RW, reset 0x0000.0000
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
reserved
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
reserved
R0
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RW
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit/Field
31:1
0
Name
reserved
R0
Type
RO
RW
Reset
0
0
Description
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
USB Module Run Mode Clock Gating Control
Value Description
0 USB module is disabled.
1 Enable and provide a clock to the USB module in Run mode.
June 12, 2014
337
Texas Instruments-Production Data