Datasheet

Register 150: Universal Asynchronous Receiver/Transmitter Power Control
(PCUART), offset 0x918
Important: The UART module does not currently provide the ability to respond to the power down
request. Setting a bit in this register has no effect on power consumption. This register
is defined for future software compatibility.
The PCUART register controls the power applied to the UART module. The function of this bit
depends on the current state of the device (Run, Sleep or Deep-Sleep mode) and value of the
corresponding bits in the RCGCUART, SCGCUART and DCGCUART registers. If the Rn, Sn, or
Dn bit of the respective RCGCUART, SCGCUART and DCGCUART registers is 1 and the device
is in that mode, the module is powered and receives a clock irrespective of what the corresponding
Pn bit in the PCUART register is.
However, if the Rn, Sn, or Dn bit of the respective RCGCUART, SCGCUART and DCGCUART
registers is 0 and the device is in that mode, then the module behaves differently depending on the
value of the corresponding Pn bit in the PCUART register. In this case, when the Pn bit is clear the
module is not powered and does not receive a clock. If the Pn bit is set, the module is powered but
does not receive a clock. The table below details the differences.
Table 5-22. Module Power Control
DescriptionPnRn, Sn or Dn Value in
Respective RCGCx,
SCGCx, or DCGCx
Register
Module is not powered and does not receive a clock. In this case, the peripheral's
state is not retained.
This is the lowest power consumption state of any peripheral since it consumes no
dynamic nor leakage current. Hardware should perform a peripheral reset if the active
mode changes and the RCGCx, SCGCx, or DCGCx register is a 1 or the P0 bit is
changed to a 1.
Software must re-initialize the peripheral when re-enabled due to the loss of state.
00
Module is powered, but does not receive a clock.
In this case, the peripheral is inactive. This is the second-lowest power consumption
of any peripheral since it consumes only leakage current.
10
Module is powered and receives a clock.X1
Universal Asynchronous Receiver/Transmitter Power Control (PCUART)
Base 0x400F.E000
Offset 0x918
Type RW, reset 0x0000.00FF
16171819202122232425262728293031
reserved
ROROROROROROROROROROROROROROROROType
0000000000000000Reset
0123456789101112131415
P0P1P2P3P4P5P6P7reserved
RWRWRWRWRWRWRWRWROROROROROROROROType
1111111100000000Reset
June 18, 2014474
Texas Instruments-Production Data
System Control