Functional Description

MCF5251 ColdFire Processor Data Sheet: Technical Data, Rev. 3

4

Freescale Semiconductor

2

Functional Description

2.1

Version 2 ColdFire Core

The Version 2 ColdFire (CF2) core consists of two independent, decoupled pipeline structures to maximize

performance while minimizing core size. The instruction fetch pipeline (IFP) is a two-stage pipeline for

prefetching instructions. The prefetched instruction stream is then gated into the two-stage operand

execution pipeline (OEP), which decodes the instruction, fetches the required operands, and then executes

the required function.

2.2

Module Inventory

Table 2 shows an alphabetical listing of the modules in the processor.

Table 2. Digital and Analog Modules

Block

Mnemonic

Block Name

Functional

Grouping

Brief Description

ATA

Advanced Technology

Attachment Controller

Connectivity

Peripheral

The ATA block is an AT attachment host interface. Its main use is to

interface with IDE hard disc drives and ATAPI optical disc drives.

ADC

Battery Level/Keypad

Analog/Digital

Converter

Analog Input

The six-channel ADC is based on the Sigma-Delta concept with 12-bit

resolution. Both the analog comparator and digital sections are integrated

in the MCF5251.

AB

Audio Bus

Audio

Interface

The audio interfaces connect to an internal bus that carries all audio data.

Each receiver places its received data on the audio bus and each

transmitter takes data from the audio bus for transmission.

AIM

Audio Interface

Audio

Interface

The audio interface module provides the necessary input and output

features to receive and transmit digital audio signals over serial audio

interfaces (IIS/EIAJ) and over digital audio interfaces (IEC958).

BROM

Bootloader

Boot ROM

The MCF5251 incorporates a ROM Bootloader, which enables booting

from UART, I2C, SPI, or IDE devices.

FlexCAN

Twin Controller Area

Network 2.0B

Communication Unit

Connectivity

Peripheral

The FlexCan module is a full implementation of the Bosch CAN protocol

specification 2.0B, which supports both standard and extended message

frames.

CSM

Chip Select Module

Connectivity

Peripheral

Three programmable chip-select outputs (CS0/CS4, CS1, and CS2)

provide signals that enable glueless connection to external memory and

peripheral circuits.

DMAC

Direct Memory

Access Controller

Module

Connectivity

Peripheral

There are four fully programmable DMA channels for quick data transfer.

eMAC

enhanced Multiply

Accumulate Module

Core

The integrated eMAC unit provides a common set of DSP operations and

enhances the integer multiply instructions in the ColdFire architecture.

MBUS

Memory Bus Interface Bus Operation The bus interface controller transfers data between the ColdFire core or

DMA and memory, peripherals, or other devices on the external bus.

MMC/SD

Multimedia

Card/Secure Digital

Interface

Flash Memory

Card Interface

The interface is Sony® Memory Stick®, SecureDigital, and Multi-Media

card compatible.

Note: The Sony Memory Interface does not support Sony MagicGate™.