index.md (1182B)
1 +++ 2 title = 'Hardware components' 3 +++ 4 # Hardware components 5 ## Von Neumann Architecture 6 7  8 9 ## Organisation of the Central Processing Unit (CPU) 10 11  12 13 14 ## Register file 15 small and fast memory block, array of storage elements 16 17 circuitry that enables data to be read from or written to any register 18 19 access circuitry: 20 21 - read 22 - enables two registers to be read at the same time 23 - has two address inputs to select registers to be read 24 - dual-ported: contents of two registers is available via two separate outputs A and B (ports) 25 - write 26 - data input C and corresponding address input for read 27 28 how to realise dual-ported memory units: 29 30 | Single memory block | Two memory blocks | 31 | --- | --- | 32 |  |  | 33 34 ## ALU 35 used to manipulate data, performs add/subtract and logic (AND, OR, XOR) 36 37 two inputs — one from register out A, one from multiplexer 38 39 multiplexer either selects register out B, or immediate value in IR 40 41 output is connected to data input of registers 42 43 