Core Coupled Memory

Some STM32 MCUs include a feature called CCMRAM (Core Coupled Memory), which is separate from the regular SRAM region.

According to the datasheet, the memory in STM32F405 is:

In the block diagram it is shown like this:

It is worth noticing a few things. As the name implies this RAM is connected directly to the MCU core but separate from the AHB bus matrix. Looking at the bus matrix:

Usage Examples

• Using CCMRAM for FreeRTOS Heap