What does instruction set architecture include?
An Instruction Set Architecture (ISA) is part of the abstract model of a computer that defines how the CPU is controlled by the software. The ISA acts as an interface between the hardware and the software, specifying both what the processor is capable of doing as well as how it gets done.
What is the meaning of PDP-11?
Programmed Data Processor-11
PDP-11 (Programmed Data Processor-11) is one of the most famous computers in computing history, one of a series manufactured by Digital Equipment Corporation ( DEC ) from the early 1960s through the mid-1990s. PDP-11, which was sold in 1970 for $10,800, was the only 16-bit computer ever made by the company.
How much did a PDP-11 cost?
The first model of PDP-11, (priced 20000 USD), named PDP-11/20, was shipped in the spring of 1970. It had word length 16 bits, speed 800 nanoseconds, the cycle time was 1.5 microseconds and the access time, 0.75 microseconds.
How many registers should the PDP 11 have?
The CPU contains eight general-purpose 16-bit registers (R0 to R7).
How much memory did a PDP-11 have?
Later-model PDP-11 processors included memory management to support virtual addressing. The physical address space was extended to 18 or 22 bits, hence allowing up to 256 KB or 4 MB of RAM.
Who created the PDP-11?
Digital Equipment Corporation
PDP-11/Manufacturers
The last machine marketed under the name “PDP” was the -16 in 1972. After the success of the PDP-8, leading hardware engineer Edson DeCastro designed a 16-bit machine under the codename “PDP-X”, which was rejected in favor of another machine, to be known as the PDP-11. DeCastro parted with DEC, and formed Data General.
Who invented PDP-11 computer?
PDP-11/Manufacturers
What is a PDP-11 70?
A 2 Kbyte, 300 nsec cache, organized as 2-way set associative, with 4-byte blocks, connected to what had been the FastBus high-speed memory interface on the PDP-11/45 CPU. The ability to support up to 4 Mbytes of main memory via a new Main Memory Bus, and changes to the CPU to allow access to that much memory.
What kind of instruction set is PDP 11?
The PDP-11 architecture is a CISC instruction set architecture (ISA) developed by Digital Equipment Corporation (DEC). It is implemented by central processing units (CPUs) and microprocessors used in PDP-11 minicomputers. It was in wide use during the 1970s, but was eventually overshadowed by the more powerful VAX-11 architecture in the 1980s.
What was the memory size of the PDP 11?
Both the PDP-11 architecture and instruction set introduced several new ideas, which influenced the design of subsequent generations of micro-processors (such as the Intel 386). The 16 bit word size enabled access to 65,536 bytes of memory (but this was expandable).
How is data stored in the PDP-11 architecture?
Thirty-two-bit data—supported as extensions to the basic architecture, e.g., floating point in the FPU Instruction Set, double-words in the Extended Instruction Set or long data in the Commercial Instruction Set —are stored in more than one format, including an unusual middle-endian format sometimes referred to as “PDP-endian”.
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: