STM32F302xx/STM32F303xx
Functional overview
3
Functional overview
3.1
ARM® Cortex™-M4F core with embedded Flash and SRAM
The ARM Cortex-M4F processor is the latest generation of ARM processors for embedded
systems. It was developed to provide a low-cost platform that meets the needs of MCU
implementation, with a reduced pin count and low-power consumption, while delivering
outstanding computational performance and an advanced response to interrupts.
The ARM Cortex-M4F 32-bit RISC processor features exceptional code-efficiency,
delivering the high-performance expected from an ARM core in the memory size usually
associated with 8- and 16-bit devices.
The processor supports a set of DSP instructions which allow efficient signal processing
and complex algorithm execution.
Its single precision FPU speeds up software development by using metalanguage
development tools, while avoiding saturation.
With its embedded ARM core, the STM32F302xx/STM32F303xx family is compatible with
all ARM tools and software.
Figure 1 and Figure 2 show the general block diagrams of the
STM32F302xx/STM32F303xx family devices.
3.2
Memory protection unit (MPU)
The memory protection unit (MPU) is used to separate the processing of tasks from the data
protection. The MPU can manage up to 8 protection areas that can all be further divided up
into 8 subareas. The protection area sizes are between 32 bytes and the whole 4 gigabytes
of addressable memory.
The memory protection unit is especially helpful for applications where some critical or
certified code has to be protected against the misbehavior of other tasks. It is usually
managed by an RTOS (real-time operating system). If a program accesses a memory
location that is prohibited by the MPU, the RTOS can detect it and take action. In an RTOS
environment, the kernel can dynamically update the MPU area setting, based on the
process to be executed.
The MPU is optional and can be bypassed for applications that do not need it.
3.3
Embedded Flash memory
All STM32F302xx/STM32F303xx devices feature up to 256 Kbytes of embedded Flash
memory available for storing programs and data. The Flash memory access time is adjusted
to the CPU clock frequency (0 wait state from 0 to 24 MHz, 1 wait state from 24 to 48 MHz
and 2 wait states above).
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