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6. Detailed Instruction Codes: Bit manimpulation and jumps

Bit manipulations also fit exactly and neatly into 20 bits. 3 bits specify the action required, 6 bits the number of the bit in the word (0..39), and 8 bits the source and destination registers.

The jumps and calls require the full 40 bits for specification of the target address. Branches fit in 20 bits, they have 12 bits available to specify the displacement from the current location. The Jump, Branch, Call and return instructions all have conditional variants, which test the state of the Carry, Zero and Sign flags.