The HP 3000 computer system

Abstract

The HP 3000 (1) is a 16-bit multiprogramming computer. Multiprogramming is facilitated through the use of a virtual memory scheme using code and data segmentation. The impetus for this machine was HP's growth in the time sharing market. The original offering in this area was the 2000A, a BASIC system using the HP 2116. This use and real-time demands from HP's other divisions led to the 3000's development. The 2100 (2), the 2116's successor and classical one-address machine, did not readily lend itself to multiprogramming, but the 3000 was designed with this in mind. From the beginning, the 3000 involved inputs from both hardware and software development teams. The end machine was designed with the operating system in mind and with a high level systems programming language (SPL) as the implementation tool for the operating system (MPE, multiprogramming executive) and all sub-systems. The Burroughs influence is evident in these choices. Separate code and data segmentation with segments of variable length is the heart of the hardware and software system. A program consists of one or more code segments and a data segment. The data segment, also known as the stack, is used for a program's global and temporary storage. It also contains a stack used for operations and procedure return addresses.