x86 - What is the purpose of CS and IP registers in Intel 8086 assembly? -

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so, question states, purpose of cs , ip registers in intel's 8086

i found explanation:

code segment (cs) 16-bit register containing address of 64 kb segment processor instructions. processor uses cs segment accesses instructions referenced instruction pointer (ip) register. cs register cannot changed directly. cs register automatically updated during far jump, far call , far return instructions.

and ip:

instruction pointer (ip) 16-bit register.

i don't understand means, if provide more "vivid" explanation, great :)

since ip 16 bit means can have 64k instructions (2^16), wasn't in 80s. expand address space have second register addresses 64k blocks. consider cs:ip 1 32 bit register capable of addressing 2^32 bytes...ie 4g on processor uses 32 bit addresses. 8086 using 20 bits of addresses, access 1m of memory.


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