Hitachi Europe Ltd has announced the H8S series of 16-bit microntrollers, with which it hopes to dominate the fast-growing 16-bit market, where it is currently number two to Intel Corp. The company claims the H8S combines the fastest 16-bit processing available with the lowest power consumption. The introduction of the family completes the company’s microcontroller offerings from low-end 4-bit devices up to 32-bit chips. The H8S is positioned as a high-end 16-bit device for products like quad-speed CD-ROM drives, bubble-jet colour printers and consumer electronic goods where battery life is an issue. It is an extension of the other H8 8-bit and 16-bit products, using many of the peripheral chips and the bus controller developed for these devices. It has the same code density so that software for H8/300H chips will run on the H8S without any changes, but does so up to two and half times faster and using only 20% more power, said the company. It has single cycle instruction execution and tight on-chip integration of memory which has reduced the amount of silicon used and level of electronic noise. First products will have 128Kb ROM and 4Kb RAM, rising to 250Kb and 6Kb, although actual levels will depend on the application; Hitachi plans to sell the H8S as application specific chips, customising them for different markets. One new feature is something called the Data Transfer Controller. This functions in the same way as a Direct Memory Access controller, automatically putting information into memory without interrupting the CPU, but it is an order of magnitude slower than direct memory access. However, it takes less silicon, so it’s cheaper and the company thinks there will be a market. Performance improvements have been gained by the addition of a hardware multiply or multiply-and-accumulate unit which takes maths-intensive application out of software and into the hardware. Power consumption has been reduced by the addition of event-driven logic that only switches when needed; and the bus has been split so that the CPU accesses peripherals only when it actually needs to talk to them. The firm has not released pricing but said the range will be 10% higher than the current 16-bit devices at the low end and 10% cheaper than the 32-bit chips, at the other end. It expects to get them on the mass market by the end of the year and said there will a variety of configurations to choose from.
