Advanced RISC Machines Ltd’s entry for this week’s Microprocessor Forum looks like a very hot property indeed: the ARM7500 is an ARM RISC core integrated with most of the functions required for a television set-top decoder box or a minimum chip count portable computer on a single chip. Prototypes of the part are being used in the Online Media Ltd video-on-demand trial in Cambridge, and it is being fabricated by VLSI Technology Inc. The ARM7500 is rated at up to 30 Dhrystone 2.1 MIPS at 33MHz, has a 4Kb cache, write buffer, memory management unit, video and sound support and input-output. System engineers can specify separate clock rates for all the subsystems. The programmable video circuitry is claimed to drive large screens and produce photographic quality, and also directly drives liquid crystal diode displays. The stereo sound subsystem has 8-bit analogue stereo sound with a digital-to-analogue converter supporting stereo headphones. The four dynamic and two read-only memory banks can be individually programmed as 32- or 16-bit storage. The input-output subsystem will drive multiple peripherals including PS/2 keyboards, mice, joysticks and other such devices; it also directly supports 16-bit PCMCIA devices. It can be clocked at 3V for driving a flat-panel display, when it dissipates just 500mW, and it powers down to idle and stop modes. Samples, in a 240-pin quad flat, pack arrive next quarter.
