When most of the minicomputer world was 16-bit, Harris Corp went a half better and chose a 24-bit word length, and so when the competition doubled everything up and went 32-bit, Harris graduated to become only the second major manufacturer after Unisys with the A series and its B5-6-7X00 predecessors to implement a 48-bit word. And, despite its diversification into 32-bit Unix systems, Harris Computer Systems remains fully committed to its 48-bit real-time H-series machines, and last week added four new models, and with them a new multiprocessor RT-VOS/MP release of its proprietary real-time virtual operating system, that supports tightly-coupled multiprocessing for the first time. And not just over two or four processors, but over as many as 12. The new models, all built in the same 100K ECL as the previous H-1000 and H-1200, are the H-900 and H-1100 uniprocessors, the H-1500 dual processor, and the H-1600 triple processor. The H-1500 is rated by the company at 10 MIPS on the single precision Whetstone benchmark, the H-1600 at 15 MIPS, 8 MIPS and 12 MIPS in double precision work. Each processor has a 40Mbyte-per-second shared memory bus and an internal 80Mbyte-per-second bus, and each has a 6Kb hierarchical cache with 75nS access memory, plus 288Kb of bulk cache with a 120nS access time. The H-1500 supports up to 50 channels and up to 512 input-output devices, of which 320 can be terminals. The H-1600 comes with 69 channels to support up to 416 terminals and 768 input-output devices in total. Up to 244 interactive terminals can be live at any time on either. Maximum disk is 20Gb on all models and integral floating point hardware is standard. The H-1500 with 12Mb and 6Kb cache per processor, 38Mbyte-per-second input-output bandwidth and the operating system is $555,000; a similarly configured H-1600 with 57Mbyte-per-second input-output bandwidth is $795,000. The H-900 and the H-1100, which can be used either standalone or as additional CPUs in MP complexes, start at $240,000 and $260,000 respectively. As well as RT/VOS-MP, Harris offers the VUE operating system, which combines Unix with VOS. Languages currently supported are Ada, C, Fortran and assembler. The machines are aimed primarily at applications in fields such as real-time simulation and process control. They are all available in the US on 90 days delivery. The H-1000 and the H-1200 will continue to be available.