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The Intel 8085 ("eighty-eighty-five") is an 8-bit microprocessor produced by Intel and introduced in March 1976. [2] It is the last 8-bit microprocessor developed by Intel. It is software-binary compatible with the more-famous Intel 8080 with only two minor instructions added to support its added interrupt and serial input/output features.
Undefined Instructions – will generate an invalid opcode (#UD) exception in all operating modes. [z] These instructions are provided for software testing to explicitly generate invalid opcodes. The opcodes for these instructions are reserved for this purpose. (3) , [aa] Intel Pentium [68] UD1 reg,r/m, [ab] UD2B reg,r/m [y] 0F B9 /r [ac] OIO, UD0,
This is a list of the instructions in the instruction set of the Common Intermediate Language bytecode. Opcode abbreviated from operation code is the portion of a machine language instruction that specifies the operation to be performed. Base instructions form a Turing-complete instruction set.
Ralf Brown's Interrupt List (aka RBIL, x86 Interrupt List, MS-DOS Interrupt List or INTER) is a comprehensive list of interrupts, calls, hooks, interfaces, data structures, CMOS settings, memory and port addresses, as well as processor opcodes for x86 machines from the 1981 IBM PC up to 2000 (including many clones), [1] [2] [nb 1] most of it still applying to IBM PC compatibles today.
Opcodes are employed in hardware devices such as arithmetic logic units (ALUs) and central processing units (CPUs) as well as in some software instruction sets. In ALUs the opcode is directly applied to circuitry via an input signal bus, whereas in CPUs, the opcode is the portion of a machine language instruction that specifies the operation to ...
For example, the Intel Pentium and the AMD Athlon implement nearly identical versions of the x86 instruction set, but they have radically different internal designs. The concept of an architecture , distinct from the design of a specific machine, was developed by Fred Brooks at IBM during the design phase of System/360 .
Using the software interrupt 21h instruction to call the MS-DOS operating system for output to the display – other samples use libc's C printf() routine to write to stdout. Note that the first example, is a 30-year-old example using 16-bit mode as on an Intel 8086. The second example is Intel 386 code in 32-bit mode.
An opcode table (also called an opcode matrix) is a visual representation of all opcodes in an instruction set. It is arranged such that each axis of the table represents an upper or lower nibble, which combined form the full byte of the opcode. Additional opcode tables can exist for additional instructions created using an opcode prefix.