4438784
Mind Map by Timothy Herschell, updated more than 1 year ago
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Created by Timothy Herschell
about 4 years ago
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Description
Machine code instructions
1 Computers can ONLY understand machine code, 0s and 1s.
Therefore, all instructions are written in machine code.
1.1 An instruction code is written in the form
0101 01 01001101
1.1.1 Op codes
1.1.1.1 The 1st four binary digits are the 'op code'. Op
codes are operations the computer has been
coded to do automatically.
1.1.1.1.1 For example, the code 0101 could make the
computer copy a register to a memory location.
1.1.2 Registers
1.1.2.1 All computers have registers. They are
a volatile area to store data.
1.1.2.1.1 Computers have different amounts of registers. If the
register number is 2 digits long, the computer has only 4.
1.1.3 Operands
1.1.3.1 The operands are the data or memory
location actually being used in the operation