Introduction
50
SLAU356I – March 2015 – Revised June 2019
Copyright © 2015–2019, Texas Instruments Incorporated
Cortex-M4F Processor
1.1
Introduction
The Cortex-M4F implementation in MSP432P4xx incorporates the following:
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Arm Cortex-M4 processor core (Revision r0p1) based on ArmV7-M architecture
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Nested Vectored Interrupt Controller (NVIC) closely integrated with the processor core to achieve low-
latency interrupt processing; supports up to 64 interrupt sources
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Multiple high-performance bus interfaces
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Low-cost debug solution with the ability to:
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Implement breakpoints through FPB
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Implement watchpoints, tracing, and system profiling through DWT
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Memory Protection Unit (MPU) supports eight regions
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IEEE 754-compliant Floating Point Unit (FPU) unit for fast floating point processing
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Bit-banding support for SRAM and peripherals
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SysTICK timer for periodic ticks
The Cortex-M4 processor features:
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Low-gate-count processor core, with low-latency interrupt processing that has:
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A subset of the Thumb instruction set, defined in the
Armv7-M Architecture Reference Manual
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Thumb-2 mixed 16- and 32-bit instruction set delivers the high performance expected of a 32-bit
Arm core in a compact memory size usually associated with 8- and 16-bit devices, for
microcontroller-class applications
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Single-cycle multiply instruction and hardware divide
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Atomic bit manipulation (bit-banding), delivering maximum memory utilization and streamlined
peripheral control
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Unaligned data access, enabling data to be efficiently packed into memory
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IEEE 754-compliant single-precision Floating-Point Unit (FPU)
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16-bit SIMD vector processing unit
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Banked stack pointer (SP)
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Hardware integer divide instructions, SDIV and UDIV
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Handler and Thread modes of processor operation
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Thumb and Debug states
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Support for interruptible-continued instructions LDM, STM, PUSH, and POP for low interrupt latency
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Automatic processor state saving and restoration for low latency Interrupt Service Routine (ISR)
entry and exit
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Support for Arm unaligned accesses
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Floating Point Unit (FPU) in the Cortex-M4F processor provides:
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32-bit instructions for single-precision (C float) data-processing operations
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Combined multiply-and-accumulate instructions for increased precision (Fused MAC).
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Hardware support for conversion, addition, subtraction, multiplication with optional accumulate,
division, and square-root
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Hardware support for denormals and all IEEE rounding modes
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32 dedicated 32-bit single precision registers, also addressable as 16 double-word registers
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Decoupled three stage pipeline
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Nested Vectored Interrupt Controller (NVIC) closely integrated with the processor core to achieve low
latency interrupt processing. Features include:
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Support for up to 64 interrupt sources
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Three bits to define the priority of each interrupt (total of eight priority levels)
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Dynamic reprioritization of interrupts