The VAX-11 is a discontinued family of 32-bit superminicomputers, running the Virtual Address eXtension (VAX) instruction set architecture (ISA), developed and manufactured by Digital Equipment Corporation (DEC). Development began in 1976.

Sep 15, 2020 · 1978年，DEC推出了PDP-11的虚拟地址扩展VirtrualAddressExtension计算机VAX-11[17]。VAX-11的地址总线有32位，为了保证市场的平稳过渡，早期的VAX-11计算机使用兼容模式运行16位程序，但是性能上要比新的32位地址程序慢。

The name VAX refers to its virtual address extension concept that allowed programs to make use of this newly available memory while still being compatible with unmodified user mode PDP-11 code. The name "VAX-11", used on early models, was chosen to highlight this capability. The VAX ISA is considered a complex instruction set computer (CISC ...

VAX是Virtual Address eXtension的簡稱。 主要因其為 16位 的 PDP-11 擴展版本，及較早應用虛擬內存管理地址空間而命名。 早期的VAX處理器同時可以兼容PDP-11的指令。

With VAX, DEC extended its PDP-11 minicomputer architecture from 16 to 32 bits. The first model in the VAX “superminicomputer” line was the VAX-11/780. The line rivaled “much more expensive mainframe computers in performance,” according to the online Computer History Museum .

VAX是Virtual Address eXtension的簡稱。主要因其為16位的PDP-11擴展版本，及較早應用虛擬内存管理地址空間而命名。早期的VAX處理器同時可以兼容PDP-11的指令。甚至事實上有時會被叫做VAX-11，以彰顯其與PDP-11的淵源和兼容性。之後的版本去掉了同PDP-11的兼容模式。

Mar 23, 2021 · 就在一年前，数字设备公司(Digital Equipment Corporation)（DEC）发布了其 32 位的 VAX 11 780 计算机。 它比市面上的 16 位机器要强大得多。 VAX 的销售迅速地超越了那些步履缓慢的竞争对手。

vax 11/780 是一台复杂且昂贵的小型计算机。 它被 RISC-I 和 RISC-II（单芯片微处理器设计）击败。 伯克利团队关于 RISC 的论文被广泛传播。

The VAX line of 32-bit “super-minicomputers” rivaled much more expensive mainframe computers. Its success made DEC the second-largest company in the industry. VAX, a “complex instruction set computer,” was widely cloned in Eastern Europe.</p>

In addition, while we have become accus- tomed to single chip microprocessors with mini- mal interfaces to probe their internal operations, the VAX 11/780 CPU spanned about 20 boards. One such board was the microcode store, which directed much of the behavior of the machine.