The TX-0, for Transistorized Experimental computer zero, but affectionately referred to as tixo (pronounced "tix oh"), was an early fully transistorized computer and contained a then-huge 64K of 18-bit words of magnetic-core memory. Construction of the TX-0 began in 1955 [1] and ended in 1956. [2] [3] [4] It was used continually through the 1960s at MIT. The TX-0 incorporated around 3,600 Philco high-frequency surface-barrier transistors, the first transistor suitable for high-speed computers. [5] The TX-0 and its direct descendant, the original PDP-1, were platforms for pioneering computer research and the development of what would later be called computer "hacker" culture. For MIT, this was the first computer to provide a system console which allowed for direct interaction, as opposed to previous computers, which required the use of punched card as a primary interface for programmers debugging their programs. [6] Members of MIT's Tech Model Railroad Club, "the very first hackers at MIT", reveled in the interactivity afforded by the console, and were recruited by Marvin Minsky to work on this and other systems used by Minsky's AI group. [7]
Designed at the MIT Lincoln Laboratory [4] largely as an experiment in transistorized design and the construction of very SMALL core memory systems, the TX-0 was essentially a transistorized version of the equally famous Whirlwind, also built at Lincoln Lab. While the Whirlwind filled an entire floor of a small flat, TX-0 fit in a single reasonably sized room and yet was somewhat faster. Like the Whirlwind, the TX-0 was equipped with a vector display system, consisting of a 12-inch oscilloscope with a working area of 7 by 7 inches connected to the 18-bit output register of the computer, allowing it to display points and vectors with a resolution up to 512×512 screen locations. [8]
The TX-0 was an 18-bit computer with a 16-bit address range. The first two bits of the machine word designated the instruction, and the remaining 16 bits are used to specify the memory location or operand for the special "operate" instruction. These two bits created four possible instructions, which included store, add, and conditional branch instructions as a basic set.
Wesley A. Clark designed the logic and Ken Olsen oversaw the engineering development. [4]
Initially a vacuum-tube computer named TX-1 was being designed to test the first large magnetic-core memory bank. However, the design was never approved and the TX-1 was never built. Instead, the TX-0 was designed for the same purpose, except using transistors. With the successful completion of the TX-0, work turned immediately to the much larger and far more complex TX-2, completed in 1958. [9] Since core memory was very expensive at the time, several parts of the TX-0 memory were cannibalized for the TX-2 project.
After a time, the TX-0 was no longer considered worth keeping at Lincoln Lab, and was "loaned" (semi-permanently) to the MIT Research Laboratory of Electronics (RLE) in July 1958, where it became a centerpiece of research that would eventually evolve into the MIT Artificial Intelligence Lab and the original computer hacker culture. Delivered from Lincoln Laboratory with only 4K of core, the machine no longer needed 16 bits to represent a storage address. After about a year and a half, the number of instruction bits was doubled to four, allowing a total of 16 instructions, and an index register was added. This dramatically improved programmability of the machine, but still left room for a later memory expansion to 8K (the four instruction bits and one-bit indexing flag left 13 bits for addressing). This newly modified TX-0 was used to develop a huge number of advances in computing, including speech and handwriting recognition, as well as the tools needed to work on such projects, including text editors and debuggers.
Meanwhile the TX-2 project was running into difficulties of its own, and several team members decided to leave the project at Lincoln Lab and start their own company - Digital Equipment Corporation (DEC).
After a short time selling "lab modules" in the form of simple logic elements from the TX-2 design, the newly formed Digital Equipment Corporation (DEC) decided to produce a "cleaned up" TX-0 design, and delivered it in 1961 as the PDP-1. A year later, DEC donated the engineering prototype PDP-1 machine to MIT. It was installed in the room next to TX-0, and the two machines would run side-by-side for almost a decade.
Significant pieces of the TX-0 are held by MIT Lincoln Laboratory. In 1983, the TX-0 was still running and is shown running a maze application in the first episode of Computer Chronicles .
As part of its use in artificial intelligence research, the computer was used to write simple western playlets and was featured in the 1961 CBS television documentary "The Thinking Machine", and in the companion book by John Pfeiffer of the same title published by the JB Lippincott Company in 1962.
A central processing unit (CPU), also called a central processor, main processor, or just processor, is the most important processor in a given computer. Its electronic circuitry executes instructions of a computer program, such as arithmetic, logic, controlling, and input/output (I/O) operations. This role contrasts with that of external components, such as main memory and I/O circuitry, and specialized coprocessors such as graphics processing units (GPUs).
Digital Equipment Corporation, using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until he was forced to resign in 1992, after the company had gone into precipitous decline.
Programmed Data Processor (PDP), referred to by some customers, media and authors as "Programmable Data Processor," is a term used by the Digital Equipment Corporation from 1957 to 1990 for several lines of minicomputers.
The PDP-1 is the first computer in Digital Equipment Corporation's PDP series and was first produced in 1959. It is famous for being the most important computer in the creation of hacker culture at the Massachusetts Institute of Technology, Bolt, Beranek and Newman and elsewhere. The PDP-1 is the original hardware for playing history's first game on a minicomputer, Steve Russell's Spacewar!
The LINC is a 12-bit, 2048-word transistorized computer. The LINC is considered by some to be the first minicomputer and a forerunner to the personal computer. Originally named the Linc, suggesting the project's origins at MIT's Lincoln Laboratory, it was renamed LINC after the project moved from the Lincoln Laboratory. The LINC was designed by Wesley A. Clark and Charles Molnar.
Whirlwind I was a Cold War-era vacuum-tube computer developed by the MIT Servomechanisms Laboratory for the U.S. Navy. Operational in 1951, it was among the first digital electronic computers that operated in real-time for output, and the first that was not simply an electronic replacement of older mechanical systems.
In computing, magnetic-core memory is a form of random-access memory. It predominated for roughly 20 years between 1955 and 1975, and is often just called core memory, or, informally, core.
The MIT Lincoln Laboratory TX-2 computer was the successor to the Lincoln TX-0 and was known for its role in advancing both artificial intelligence and human–computer interaction. Wesley A. Clark was the chief architect of the TX-2.
The IBM 7090 is a second-generation transistorized version of the earlier IBM 709 vacuum tube mainframe computer that was designed for "large-scale scientific and technological applications". The 7090 is the fourth member of the IBM 700/7000 series scientific computers. The first 7090 installation was in December 1959. In 1960, a typical system sold for $2.9 million or could be rented for $63,500 a month.
The PDP-6, short for Programmed Data Processor model 6, is a computer developed by Digital Equipment Corporation (DEC) during 1963 and first delivered in the summer of 1964. It was an expansion of DEC's existing 18-bit systems to use a 36-bit data word, which was at that time a common word size for large machines like IBM mainframes. The system was constructed using the same germanium transistor-based System Module layout as DEC's earlier machines, like the PDP-1 and PDP-4.
The history of computing hardware starting at 1960 is marked by the conversion from vacuum tube to solid-state devices such as transistors and then integrated circuit (IC) chips. Around 1953 to 1959, discrete transistors started being considered sufficiently reliable and economical that they made further vacuum tube computers uncompetitive. Metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology subsequently led to the development of semiconductor memory in the mid-to-late 1960s and then the microprocessor in the early 1970s. This led to primary computer memory moving away from magnetic-core memory devices to solid-state static and dynamic semiconductor memory, which greatly reduced the cost, size, and power consumption of computers. These advances led to the miniaturized personal computer (PC) in the 1970s, starting with home computers and desktop computers, followed by laptops and then mobile computers over the next several decades.
Incompatible Timesharing System (ITS) is a time-sharing operating system developed principally by the MIT Artificial Intelligence Laboratory, with help from Project MAC. The name is the jocular complement of the MIT Compatible Time-Sharing System (CTSS).
Computer Science and Artificial Intelligence Laboratory (CSAIL) is a research institute at the Massachusetts Institute of Technology (MIT) formed by the 2003 merger of the Laboratory for Computer Science (LCS) and the Artificial Intelligence Laboratory. Housed within the Ray and Maria Stata Center, CSAIL is the largest on-campus laboratory as measured by research scope and membership. It is part of the Schwarzman College of Computing but is also overseen by the MIT Vice President of Research.
Wesley Allison Clark was an American physicist who is credited for designing the first modern personal computer. He was also a computer designer and the main participant, along with Charles Molnar, in the creation of the LINC computer, which was the first minicomputer and shares with a number of other computers the claim to be the inspiration for the personal computer.
The PDP-5 was Digital Equipment Corporation's first 12-bit computer, introduced in 1963.
Alan Kotok was an American computer scientist known for his work at Digital Equipment Corporation and at the World Wide Web Consortium (W3C). Steven Levy, in his book Hackers: Heroes of the Computer Revolution, describes Kotok and his classmates at the Massachusetts Institute of Technology (MIT) as the first true hackers.
The surface-barrier transistor is a type of transistor developed by Philco in 1953 as an improvement to the alloy-junction transistor and the earlier point-contact transistor. Like the modern Schottky transistor, it offered much higher speed than earlier transistors and used metal–semiconductor junctions, but unlike the schottky transistor, both junctions were metal–semiconductor junctions.
A transistor computer, now often called a second-generation computer, is a computer which uses discrete transistors instead of vacuum tubes. The first generation of electronic computers used vacuum tubes, which generated large amounts of heat, were bulky and unreliable. A second-generation computer, through the late 1950s and 1960s featured circuit boards filled with individual transistors and magnetic-core memory. These machines remained the mainstream design into the late 1960s, when integrated circuits started appearing and led to the third-generation computer.
Philco was one of the pioneers of transistorized computers, also known as second generation computers. After the company developed the surface barrier transistor, which was much faster than previous point-contact types, it was awarded contracts for military and government computers. Commercialized derivatives of some of these designs became successful business and scientific computers. The TRANSAC Model S-1000 was released as a scientific computer. The TRANSAC S-2000 mainframe computer system was first produced in 1958, and a family of compatible machines, with increasing performance, was released over the next several years.
Div. 6 - Lincoln Lab MIT
Development of the TX-0 at MIT - participants include Doug Ross and Harrison (Dit) Morse, Electronic Systems Group alumni, interview conducted by Gordon Bell.