Reduced Instruction Set Computing

The Cortex RISC Processor is used in several Assured Systems products.

Reduced instruction set computing, or RISC, is a CPU design strategy based on the insight that simplified (as opposed to complex) instructions can provide higher performance if this simplicity enables much faster execution of each instruction.

Some aspects attributed to the first RISC-labeled designs around 1975 include the observations that the memory-restricted compilers of the time were often unable to take advantage of features intended to facilitate manual assembly coding, and that complex addressing modes take many cycles to perform due to the required additional memory accesses. It was argued that such functions would be better performed by sequences of simpler instructions if this could yield implementations small enough to leave room for many registers, reducing the number of slow memory accesses. In these simple designs, most instructions are of uniform length and similar structure, arithmetic operations are restricted to CPU registers and only separate load and store instructions access memory. These properties enable a better balancing of pipeline stages than before, making RISC pipelines significantly more efficient and allowing higher clock frequencies.

RISC designs have led to a number of successful platforms and the ARM architecture dominates the market for low power and low cost embedded systems (typically 100–1200 MHz in 2011). ARM Ltd, which licenses intellectual property rather than manufacturing chips, reported that 10 billion licensed chips had been shipped as of early 2008. The various generations, variants and implementations of the ARM core are deployed in over 90% of mobile electronics devices, including almost all modern mobile phones, mp3 players and portable video players. Some high profile examples are:

 • Apple iPods
 • Apple iPhone and iPod Touch
 • Apple iPad
 • Palm and PocketPC PDAs and smartphones
 • RIM BlackBerry email devices, smartphones
 • Microsoft Windows Mobile
 • Nintendo Game Boy Advance
 • Nintendo DS
 • Sony Network Walkman
 • Android smartphones, tablets

Assured Systems can supply a whole range of RISC-based products including single board computers, touchscreen human machine interfaces, and embedded computer systems.  Please call technical sales on 01785 87 90 50 to discuss your application and seek advice.  You can find all our RISC products by browsing through our product portfolio at www.assured-systems.co.uk.