MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
17-1
Chapter 17
ColdFire Flash Module (CFM)
17.1
Introduction
17.1.1
Overview
The ColdFire Flash Module (CFM) is a non-volatile memory (NVM) module for integration with a CPU.
The CFM provides 256 Kbytes of 32-bit flash memory serving as electrically erasable and programmable,
non-volatile memory. The flash memory is ideal for program and data storage for single-chip applications,
allowing for field reprogramming without requiring external programming voltage sources. The
MCF52235 incorporates SuperFlash
®
technology licensed from SST.
The common flash bus interface executes read operations to the flash memory using one or two system
bus cycles to access each flash physical block, with access latency depending on the factory setting of the
CLKSEL bits in the CFMCLKSEL register. Flash physical blocks are interleaved between odd and even
addresses to form a flash logical block. Interleaving allows back-to-back read operations to the flash
memory at an effective access rate of one system bus cycle per word after the initial two-cycle access if
the CLKSEL bits are not set for single cycle access.
It is not possible to read from any flash logical block while the same logical block is being erased,
programmed, or verified. Flash logical blocks are divided into multiple logical pages that can be erased
separately. An erased bit reads 1 and a programmed bit reads 0.
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60
