VAX (Virtual Address eXtension)

The VAX (Virtual Address eXtension) was a line of minicomputers developed and manufactured by Digital Equipment Corporation (DEC) in the 1970s and 1980s. The VAX-11/780, introduced on October 25, 1977, was the first of a successful range of computers that followed the basic architecture of the PDP-11 series but with an extended address space that allowed it to address up to 4 gigabytes of physical memory.

The VAX was a 32-bit system, with 32-bit instructions and 32-bit registers. It was also one of the first minicomputers to offer a virtual memory system, which allowed programs to address more memory than was physically present in the system.

The VAX series was eventually succeeded by the Alpha series of computers, which were based on a different architecture.

What is VAX architecture?

The VAX architecture was developed by Digital Equipment Corporation (DEC) in the late 1970s. The first VAX model, the VAX 11/780, was released in 1977.

The VAX architecture is a 32-bit instruction set architecture (ISA) that is compatible with the earlier 16-bit PDP-11 ISA. The VAX architecture was designed to extend the PDP-11 ISA while still providing backward compatibility.

The VAX architecture includes a number of features that were designed to improve performance and address the needs of larger and more complex programs. These features include:

- Support for virtual memory
- A rich set of instructions for integer and floating-point arithmetic
- Support for high-performance I/O devices

The VAX architecture was widely used in the 1980s and 1990s. It was used in a variety of applications, including scientific computing, engineering, and business. Who remembers the VAX minicomputer icon of the 1980s? The VAX minicomputer icon of the 1980s was a popular computer at the time. It was known for its simple design and ease of use.

How fast was a VAX 11 780?

The VAX 11/780 was a 32-bit minicomputer introduced by Digital Equipment Corporation (DEC) in 1977. It was based on the earlier VAX 11/750 model and was the first VAX model to use the CMOS process. The VAX 11/780 was succeeded by the VAX 8600 in 1984.

The VAX 11/780 had a maximum clock speed of 10 MHz and a memory capacity of 1 megabyte (MB). It could be configured with up to eight central processing units (CPUs) and could be expanded with up to four additional memory modules. Is the PDP-11 still in use? Yes, the PDP-11 is still in use. It is a popular choice for embedded systems and industrial control applications, due to its robustness and flexibility.

What killed Digital Equipment Corporation?

It is difficult to pinpoint a single event or change that killed Digital Equipment Corporation (DEC), as the company's decline was the result of a perfect storm of sorts. Among the factors that contributed to DEC's demise were the following:

- The rise of the personal computer: This was a major blow to DEC, as the company was slow to adapt to the changing market and failed to produce a viable PC product.

- The advent of the Internet: The Internet created a new landscape in which DEC was not well-positioned to compete.

- The rise of Microsoft: Microsoft's dominance in the software market was another contributing factor to DEC's decline.

- The company's own missteps: DEC made a number of strategic errors that ultimately hurt the company. For example, the company invested heavily in the development of the Alpha chip, which was ultimately a failure.