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Overview
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
1-11
storage for single-chip applications, allowing for field reprogramming without requiring an external high
voltage source. The CFM interfaces to the ColdFire core through an optimized read-only memory
controller which supports interleaved accesses from the 2-cycle flash arrays. A backdoor mapping of the
flash memory is used for all program, erase, and verify operations, as well as providing a read datapath for
the DMA. Flash memory may also be programmed via the EzPort, which is a serial flash programming
interface that allows the flash to be read, erased and programmed by an external controller in a format
compatible with most SPI bus flash memory chips. This allows easy device programming via Automated
Test Equipment or bulk programming tools.
1.4.5
Cryptography Acceleration Unit
The MCF52235 device incorporates two hardware accelerators for cryptographic functions. First, the
CAU is a coprocessor tightly-coupled to the V2 ColdFire core that implements a set of specialized
operations to increase the throughput of software-based encryption and message digest functions,
specifically the DES, 3DES, AES, MD5 and SHA-1 algorithms. Second, a random number generator
provides FIPS-140 compliant 32-bit values to security processing routines. Both modules supply critical
acceleration to software-based cryptographic algorithms at a minimal hardware cost.
1.4.6
Power Management
The MCF52235 incorporates several low-power modes of operation which are entered under program
control and exited by several external trigger events. An integrated power-on reset (POR) circuit monitors
the input supply and forces an MCU reset as the supply voltage rises. The low voltage detector (LVD)
monitors the supply voltage and is configurable to force a reset or interrupt condition if it falls below the
LVD trip point.
1.4.7
FlexCAN
The FlexCAN module is a communication controller implementing version 2.0 of the CAN protocol parts
A and B. The CAN protocol can be used as an industrial control serial data bus, meeting the specific
requirements of reliable operation in a harsh EMI environment with high bandwidth. This instantiation of
FlexCAN has 16 message buffers.
1.4.8
UARTs
The MCF52235 has three full-duplex UARTs that function independently. The three UARTs can be
clocked by the system bus clock, eliminating the need for an external clock source. On smaller packages,
the third UART is multiplexed with other digital I/O functions.
1.4.9
I
2
C Bus
The I
2
C bus is a two-wire, bidirectional serial bus that provides a simple, efficient method of data exchange
and minimizes the interconnection between devices. This bus is suitable for applications requiring
occasional communications over a short distance between many devices on a circuit board.
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