Memory Model
100
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Cortex
®
-M4F Processor
Table 1-15. Memory Map (continued)
Start
End
Description
0x4404.0000
0x4404.FFFF
Reserved (64KB)
0x4405.0000
0x4405.0FFF
LCD
0x4405.1000
0x4405.3FFF
Reserved
0x4405.4000
0x4405.4FFF
EPHY 0
0x4405.5000
0x5FFF.FFFF
Reserved
0x6000.0000
0xDFFF.FFFF
EPI0 mapped peripheral and RAM
Private Peripheral Bus
0xE000.0000
0xE000.0FFF
Instrumentation Trace Macrocell (ITM)
0xE000.1000
0xE000.1FFF
Data Watchpoint and Trace (DWT)
0xE000.2000
0xE000.2FFF
Flash Patch and Breakpoint (FPB)
0xE000.3000
0xE000.DFFF
Reserved
0xE000.E000
0xE000.EFFF
Cortex-M4F Peripherals (SysTick, NVIC, MPU, FPU, and SCB)
0xE000.F000
0xE003.FFFF
Reserved
0xE004.0000
0xE004.0FFF
Trace Port Interface Unit (TPIU)
0xE004.1000
0xE004.1FFF
Embedded Trace Macrocell (ETM)
0xE004.2000
0xFFFF.FFFF
Reserved
1.5.1 Memory Regions, Types, and Attributes
The memory map and the programming of the MPU split the memory map into regions. Each region has a
defined memory type, and some regions have additional memory attributes. The memory type and
attributes determine the behavior of accesses to the region.
The memory types are:
•
Normal: The processor can order transactions for efficiency and perform speculative reads.
•
Device: The processor preserves transaction order relative to other transactions to Device or Strongly
Ordered memory.
•
Strongly Ordered: The processor preserves transaction order relative to all other transactions.
The different ordering requirements for Device and Strongly Ordered memory mean that the memory
system can buffer a write to Device memory but must not buffer a write to Strongly Ordered memory.
An additional memory attribute is Execute Never (XN), which means the processor prevents instruction
accesses. A fault exception is generated only when an instruction is executed from an XN region.
1.5.2 Memory System Ordering of Memory Accesses
For most memory accesses caused by explicit memory access instructions, the memory system does not
ensure that the order in which the accesses complete matches the program order of the instructions,
providing the order does not affect the behavior of the instruction sequence. Normally, if correct program
execution depends on two memory accesses completing in program order, software must insert a memory
barrier instruction between the memory access instructions (see
However, the memory system does ensure ordering of accesses to Device and Strongly Ordered memory.
For two memory access instructions A1 and A2, if both A1 and A2 are accesses to either Device or
Strongly Ordered memory, and if A1 occurs before A2 in program order, A1 is always observed before A2.
1.5.3 Behavior of Memory Accesses
shows the behavior of accesses to each region in the memory map. See
for
more information on memory types and the XN attribute. MSP432E4 devices may have reserved memory
areas within the address ranges listed in
(see
for more information).