What is the 80x86 processor family?
6.14 Summary The 80x86 processor family provides a rich CISC (complex instruction set computer) instruction set. Members of the 80x86 processor family are generally upward compatible, meaning successive processors execute all the instructions of the previous chips.
What are the 8086 multiplication instructions?
The multiplication instructions provide you with your ?rst taste of irregularity in the 8086’s instruction set. Instructions like add, adc, sub, sbb, and many others in the 8086 instruction set use a mod-reg-r/m byte to support two operands.
Why does the 8086 use Reg bits?
Unfortunately, there aren’t enough bits in the 8086’s opcode byte to support all instructions, so the 8086 uses the reg bits in the mod-reg-r/m byte as an opcode extension. For example, inc, dec, and negdo not require two operands, so the 80x86 CPUs use the reg bits as an extension to the eight bit opcode.
What are the logical instructions for the 80386 processor?
The logical instructions are and, or, xor, test, and not; the rotates are ror, rol, rcr,and rcl; the shift instructions are shl/sal, shr, and sar. The 80386 and later processors provide an even richer set of operations. These are bt, bts, btr, btc, bsf, bsr, shld, shrd, and the conditional set instructions (setcc).
The Intel 8086 Instruction Set