Datasheet

Timer Peripheral Present (PPWD) register, provide information on how many of each type of
module are included on the device. Finally, information about the capabilities of the on-chip
peripherals are provided at offset 0xFC0 in each peripheral's register space in the Peripheral
Properties registers, such as the GPTM Peripheral Properties (GPTMPP). In addition, there are
four unique identifier registers, Unique Identifier n (UNIQUEIDn), that provide a 128-bit unique
identifier for each device that cannot be modified.
5.2.2 Reset Control
This section discusses aspects of hardware functions during reset as well as system software
requirements following the reset sequence.
5.2.2.1 Reset Sources
The TM4C129ENCPDT microcontroller has the following reset sources:
1. Power-on reset (POR) (see page 229).
2. External reset input pin (RST) assertion (see page 230).
3. A brown-out detection of V
DDA
(analog voltage source) or V
DD
(external voltage source) dropping
below its acceptable operating range. (see page 231).
4. Software-initiated reset (with the software reset registers) (see page 233).
5. A watchdog timer reset condition violation (see page 233).
6. Hibernation module event
7. A software restart initiated through a Hardware System Service Request (HSSR)
8. MOSC failure (see page 235).
Table 5-2 provides a summary of results of the various reset operations. Note that the external RST
pin, the Brown-out detection unit, the HIB module and watchdog timer can all be programmed to
generate either a Power-On Reset (POR) or system reset depending on how the Reset Behavior
Control (RESBEHAVCTL) register at offset 0x1D8 is programmed.
Table 5-2. Reset Sources
On-Chip Peripherals Reset?JTAG Reset?Core Reset?Reset Source
YesYesYesExternally Generated
Power-On Reset
YesPin Configuration OnlyYesRST pin Power-On Reset
YesPin Configuration OnlyYesRST pin System Reset
YesPin Configuration OnlyYesBrown-Out Power-On Reset
YesPin Configuration OnlyYesBrown-Out System Reset
YesPin Configuration OnlyYesSoftware System Reset
Request using the
SYSRESREQ bit in the APINT
register.
NoNoYesSoftware System Reset
Request using the
VECTRESET bit in the APINT
register.
June 18, 2014228
Texas Instruments-Production Data
System Control