Functional Description
195
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
System Control
4.1
Functional Description
The System Control module provides the following capabilities:
•
Device identification (see
)
•
Configurable control of reset, power, and clock sources
•
System control (run, sleep, and deep-sleep modes) (see
4.1.1 Device Identification
Read-only registers in the system control module provide information about the microcontroller, such as
version, part number, pin count, operating temperature range and available peripherals on the device. The
Device Identification 0 (see
) and Device Identification 1 (see
) registers provide details about
the device version, package, temperature range, and so on. The Peripheral Present registers starting at
system control offset 0x300, such as the Watchdog 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 the register space of each peripheral
in the Peripheral Properties registers, such as the GPTM Peripheral Properties (GPTMPP). In addition,
four unique identifier registers, Unique Identifier n (UNIQUEIDn), provide a 128-bit unique identifier for
each device that cannot be modified.
4.1.2 Reset Control
This section discusses aspects of hardware functions during reset as well as system software
requirements following the reset sequence.
4.1.2.1
Reset Sources
The MSP432E4 microcontroller has the following reset sources:
1. Power-on reset (POR) (see
2. External reset input pin (RST) assertion (see
)
3. A brownout detection of V
DDA
(analog voltage source) or V
DD
(external voltage source) dropping below
its acceptable operating range (see
4. Software-initiated reset (with the software reset registers) (see
)
5. A watchdog timer reset condition violation (see
)
6. Hibernation module event
7. A software restart initiated through a Hardware System Service Request (HSSR)
8. MOSC failure (see
)
provides a summary of results of the various reset operations. The external RST pin, the
brownout 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 4-1. Reset Sources
Reset Source
Core Reset?
JTAG Reset?
On-Chip Peripherals
Reset?
Externally generated POR
Yes
Yes
Yes
RST pin POR
Yes
Pin configuration only
Yes
RST pin system reset
Yes
Pin configuration only
Yes
Brownout POR
Yes
Pin configuration only
Yes
Brownout system reset
Yes
Pin configuration only
Yes
Software system reset request using the
SYSRESREQ bit in the APINT register
Yes
Pin configuration only
Yes
Software system reset request using the
VECTRESET bit in the APINT register
Yes
No
No