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السلام علیکم
The Lab / 02
Two small registers. One physical address. Explore how segment and offset values work together in the 8086.
02 / A look inside the machine
Enter 1–4 hexadecimal digits (0–9, A–F) in each field.
12340h + 0010h = 12350h
Physical address · 20-bit bus
74,576 in decimal
10h means 16 in decimal. Multiplying by 10h shifts the segment one hexadecimal place to the left.
What is happening?
On the original 8086, a segment value identifies a starting point in memory. Multiplying it by 16 and adding an offset gives the address placed on the 20-bit address bus.
The takeaway
Different segment and offset pairs can refer to the same physical location. On the original 8086, addresses above FFFFFh wrap around within the 1 MiB address space.