What is PDP-8?

The

PDP-8 was a 12-bit minicheter made by Digital Equipment Corporation (Dec) from the mid-sixties to the late 70 years. It included a simple processor, basic memory and at least one input/output device (I/O) such as teletepe. These computers were often used for business applications and also for inspection of industrial machines and scientific experiments.

, unlike many modern PDP-8 computers, did not include pre-installed operating system software. A simple program could be based on the use of switches on the front panel of the machine. It was usually a trigger loader, which then transferred other software from the data storage device; Paper tape and magnetic tape were at that time the most common PDP storage medium. Compilators and interpreters were available for a number of computer programming languages, including basic, dibol, focal and FORTRAN. Several operating systems were also developed for this machine; OS/8 was one of the most commonly used.

many different8 models were made. For example, PDP-8/E introduced an improved memory controller to support virtual machines. Model /A increased the capacity of the basic memory above the limit of 32K. Other models often added instructions and registers. Over time, new types of I/O devices, including disk units, cassette strip units and analogue to digital converters, have also been introduced.

Early PDP-8 systems were built with individual transistors, diodes and resistors. At the end of the sixties, many of these components replaced the integrated TTL circuits, which simplified production. In the final move to save energy and streamline design, their integrated CMOS integrated circuits were used at the end of the 70s.

PDP-8 was very popular at the beginning of 70 years; It was the first powerful computer that can be purchased cheaply than rent. Many companies used them to operate their business operations, included AccountIng and Inventory Control. Some were even rented to the public for an hour in computer centers; Programming, text processing and gaming were common tasks. PDP means a programmable data processor; Dec usually avoided the computer , which was often associated with a large and expensive range of machines. By the end of the 1970s, smaller microcomputers with lower prices from Apple and Tandy took most of their market.

PDP-8 processor, memory and control circuits are not very complex according to today's standards; Enthusiasts implemented it all in a single FPGA chip, so cheap hardware "clones" makes reality. There are several software emulators that can run PDP programs. Much of the original DEC documentation is also available on the Internet. One site even offers online access to the real, running PDP-8 system. Many of these computer vintage still work; Some continue their original duties while others can be purchased from auctiont page and privateCollectors.