1.1. Overview

ARM720T is a general‑purpose 32-bit microprocessor with 8KB cache, enlarged write buffer and Memory Management Unit (MMU) combined in a single chip. The CPU within ARM720T is the ARM7TDMI. The ARM720T is software compatible with the ARM processor family.

ARM720T is a fully static part and has been designed to minimize power requirements. This makes it ideal for portable applications, where both these features are essential.

The ARM720T architecture is based on Reduced Instruction Set Computer (RISC) principles, and the instruction set and related decode mechanism are greatly simplified compared with microprogrammed Complex Instruction Set Computers (CISC).

The on-chip mixed data and instruction cache, together with the write buffer, substantially raise the average execution speed and reduce the average amount of memory bandwidth required by the processor. This allows the external memory to support additional processors or Direct Memory Access (DMA) channels with minimal performance loss.

The allocation of virtual addresses with different task ID improves performance in task switching operations with the cache enabled. These relocated virtual addresses are monitored by the EmbeddedICE block.

The MMU supports a conventional two-level, page-table structure and a number of extensions which make it ideal for embedded control, UNIX and object-oriented systems.

The memory interface has been designed to allow the performance potential to be realized without incurring high costs in the memory system. Speed-critical control signals are pipelined to allow system control functions to be implemented in standard low-power logic, and these control signals permit the exploitation of paged mode access offered by industry standard DRAMs.

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