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How much memory did a PDP 10 have?
with a capacity of 32 to 256 kWords of magnetic core memory (the picture on the right hand side of the introduction shows six of these cabinets). The processors used in the DECSYSTEM-20 (2040, 2050, 2060, 2065), commonly but incorrectly called “KL20”, use internal memory, mounted in the same cabinet as the CPU.
What happened Digital Equipment Corporation?
DEC was acquired in June 1998 by Compaq in what was at that time the largest merger in the history of the computer industry. During the purchase, some parts of DEC were sold to other companies; the compiler business and the Hudson, Massachusetts facility, were sold to Intel.
How does the PDP-11 instruction set work?
The key to understanding the PDP-11 instruction set is in understanding how the addressing modes work. In a PDP-11 instruction, the source and/or destination operands can refer to either a location in main memory or a register. When the instruction is assembled, just 6 bits are set aside to represent these operands.
How does the PDP-11 assembly language work?
Each PDP-11 machine language instruction has a length of 16 bits (1 word) and is always located at an even memory location. The flow of execution of a program is managed by the Program Counter (PC) register. This register stores the 16 bit address of the next instruction that is to be executed. It works like this:
How are byte operands manipulated in the PDP-11?
The PDP-11 includes a full complement of instructions that manipulate byte operands. Since all PDP-11 addressing is byte-oriented, byte manipulation addressing is straightforward. Byte instructions with autoincrement or autodecrement direct addressing cause the specified register to be modified by one to point to the next byte of data.
How long has the PDP-11 been in use?
This year represents the 60th anniversary of the founding of the company that produced the PDP-11. It is also 40 years since this paper was written, so I thought it would be entertaining to review Bell’s retrospective through the lens of our own 20/20 hindsight.