ArrowARM Guide - Embedded Developer

10 |ARM920THigh-Performance and Low-Power Platform OSThe ARM9TDMI processor core is a Harvard architecture device implemented using a five-stage pipeline consisting offetch, decode, execute, memory, and write stages. It can be provided as a standalone core that can be embedded intomore complex devices. The standalone core has a simple bus interface that allows you to design your own caches andmemory systems around it.The ARM920T processor is a member of the ARM9TDMI family of general-purpose microprocessors, which includes:• ARM9TDMI (core)• ARM940T (core plus cache and protection unit)• ARM920T (core plus cache and MMU)ARM920T Application Support Features The ARM9TDMI family of microprocessors supports both the32-bit ARM and 16-bit Thumb ® instruction sets, allowing youto trade off between high performance and high code density.The ARM920T processor is a Harvard cache architectureprocessor that is targeted at multi-programmer applicationswhere full memory management, high performance, and lowpower are all-important. The separate instruction and datacaches in this design are 16 KB each in size, with an eight-wordline length. The ARM920T processor implements an enhancedARM architecture v4 MMU to provide translation and accesspermission checks for instruction and data addresses.The ARM920T processor supports the ARM debug architectureand includes logic to assist in both hardware and softwaredebug. The ARM920T processor also includes support forcoprocessors, exporting the instruction and data buses alongwith simple handshaking signals.The ARM920T’s interface to the rest of the system is overunified address and data buses. This interface enablesimplementation of an Advanced Microcontroller Bus Architecture(AMBA), an Advanced System Bus (ASB), or an AdvancedHigh-performance Bus (AHB) scheme either as a fully compliantAMBA bus master, or as a slave for production test. TheARM920T processor also has a Tracking ICE mode, whichallows an approach similar to a conventional ICE mode ofoperation.The ARM920T processor supports the addition of anEmbedded Trace Macrocell (ETM) for real-time tracing ofinstructions and data.ARM920T16KInstructioncacheMMUETM InterfaceARM9TDMIcoreWrite bufferControl Logic and Bus Interface UnitCoprocessorInterface16KDatacacheMMUAMBA AHB InterfaceArrow Electronics ARM Solutions1-866-910-3650