The segment address by the segment value 2010H can have offset value from 0000 H to FFFFH within it, ie. Maximum 64K locations may be accommodated in the segment.

The physical address range for this segment is from 20100 H to 300FFH .

The segment register indicates the base address of a particular segment and CS , DS , SS and ES are used to keep the segment address.

The offset indicates the distance of the required memory location in the segment from the base address, and the offset may be the content of register IP , BP , SI , DI and SP .

Once the opcode is fetched and decoded, the external bus becomes free while the Execution Unit is executing the instruction.

While the fetched instruction is executed internally, the external bus is used to fetch the machine code of the next instruction and arrange it in a queue called as predecoded instruction byte queue.

This is a 6 byte long queue, works in first-in first-out policy.

While the opcode is fetched by the bus interface unit (BIU), the execution unit (EU) executes the previously decoded instruction concurrently.