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Is PDP-11 byte addressable?
The PDP-11 is a byte addressed machine but it has a 16 bit data bus. If you issue a word read to address 100, it will return you the two bytes at 100 and 101. The PDP-11 is little endian so the byte at 100 is the low byte.
How many registers should the PDP-11 have?
In other words, the byte ordering was little endian. The top 4096 words in the memory space (from 177777 downwards) were reserved for the system, giving 28,672 words for programming. The PDP-11 had 8 16-bit registers that could be used by the programmer.
What is the maximum physical address on a PDP-11?
The physical address space was extended to 18 or 22 bits, hence allowing up to 256 KB or 4 MB of RAM.
What does PDP-11 stand for?
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.
Is PDP-11 is a supercomputer?
The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC’s most successful product lines.
Does Intel use ARM?
Under the hood, the main difference between an Intel and ARM-based CPU is the type of instruction that each device understands. ARM-based CPUs are RISC (Reduced Instruction Set Computer) devices and Intel CPUs are CISC (Complex Instruction Set Computer) devices.
Who invented PDP-11 computer?
Digital Equipment Corporation
PDP-11/Inventors
It seems however that the designed by de Castro PDP-X has little relationship to DEC’s eventual 16-bit architecture, the PDP-11. Gordon Bell, the vice president of research in DEC, was involved with recommending what became the PDP-11, while the actual design was made by Harold McFarland.
When did the PDP-11 architecture come into use?
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. Sixteen-bit words are stored little-endian (with least significant bytes first).
Who is the developer of the PDP-11 Isa?
The PDP-11 architecture is an 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.
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.
How are the bytes specified in the PDP-11?
The PDP-11 operates on bytes and words. Bytes are specified by a register number—identifying the register’s low-order byte—or by a memory location. Words are specified by a register number or by the memory location of the low-order byte, which must be an even number.