mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 545

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

Chapter 24
External Bus Interface (Mini-FlexBus)
24.1 Introduction
This chapter describes external bus data transfer operations and error conditions. It
describes transfers initiated by the core processor (or any other bus master) and includes
detailed timing diagrams showing the interaction of signals in supported bus operations.
The Mini-FlexBus is a subset of the FlexBus module found on other ColdFire
microprocessors. The Mini-FlexBus minimizes package pin-outs while maintaining a
high level of configurability and functionality.
24.1.1 Overview
A multi-function external bus interface called the Mini-FlexBus interface controller is
provided on the device with basic functionality of interfacing to slave-only devices. It can
be directly connected to the following asynchronous or synchronous devices with little or
no additional circuitry:
For asynchronous devices, a simple chip-select based interface can be used.
The Mini-FlexBus interface has up to two general purpose chip-selects, FB_CS[1:0]. The
actual number of chip selects available depends upon the device and its pin configuration.
Freescale Semiconductor, Inc.
• External ROMs
• Flash memories
• Programmable logic devices
• Other simple target (slave) devices
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Preliminary
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