NXP Semiconductors MKL25Z128VLK4 - KL25 Sub-Family Reference Manual, Rev. 3, September

Chapter 26
Flash Memory Controller (FMC)
26.1 Introduction
The Flash Memory Controller (FMC) is a memory acceleration unit that provides:
• an interface between bus masters and the 32-bit program flash memory.
• a buffer and a cache that can accelerate program flash memory data transfers.
26.1.1 Overview
The Flash Memory Controller manages the interface between bus masters and the 32-bit
program flash memory. The FMC receives status information detailing the configuration
of the flash memory and uses this information to ensure a proper interface. The FMC
supports 8-bit, 16-bit, and 32-bit read operations from the program flash memory. A write
operation to program flash memory results in a bus error.
In addition, the FMC provides two separate mechanisms for accelerating the interface
between bus masters and program flash memory. A 32-bit speculation buffer can prefetch
the next 32-bit flash memory location, and a 4-way, 4-set program flash memory cache
can store previously accessed program flash memory data for quick access times.
26.1.2 Features
The FMC's features include:
• Interface between bus masters and the 32-bit program flash memory:
• 8-bit, 16-bit, and 32-bit read operations to nonvolatile flash memory.
• Acceleration of data transfer from the program flash memory to the device:
KL25 Sub-Family Reference Manual, Rev. 3, September 2012
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