MCF548x Reference Manual, Rev. 3
Freescale Semiconductor 10-1

Chapter 10

Internal Clocks and Bus Architecture

10.1 Introduction

This chapter describes the clocking and internal buses of the MCF548x and discusses the main functional
blocks controlling the XL bus and the XL bus arbiter.

10.1.1 Block Diagram

Figure 10-1 shows a top-level block diagram of the MCF548x products.
*Available in MCF5485, MCF5484, MCF5483, and MCF5482 devices.
**Available in MCF5485, MCF5484, MCF5481, and MCF5480 devices.
***Available in MCF5485, MCF5483, and MCF5481 devices.
Figure 10-1. MCF548x Internal Bus Architecture
PLL DDR SDRAM
Memory
Controller
PCI I/O Interface and Ports
CommBus
USB 2.0
PHY*
Perpheral Communications I/O Interface & Ports
FEC1**PSC x 4I2CFEC0 USB 2.0
DEVICE*
Interface
FlexBus
Controller
FlexBus
Interface
PCI Interface
& FIFOs
Master/Slave
Interface
ColdFire V4e Core
FPU, MMU
EMAC
32K D-cache
32K I-cache
FlexCAN
x 2
Slave
Bus
DSPI
Perpheral I/O Interface & Ports
Communications
I/O Subsystem
Interrupt
Controller
XL Bus
Arbiter
System
Integration Unit
DMA
Read
DMA
Write
Multichannel DMA
Master Bus Interface and FIFOs
Slice
Timers x 2
GP
Timers x 4
Watchdog
Timer
PCI 2.2
Controller
Cryptography
32K System
SRAM
Crypto
R/W
XL Bus
Read/Write
XL Bus
Accelerator***