The address bus in the 8085 is 16 bits wide.
Physical address in the 8086/8088 is {Selected Segment Register} * 16 + {Effective Offset Address}. It is a 20-bit address .
The 8086/8088 has an internal 20-bit address bus and 16-bit data bus. Externally, the address bus is 20-bits, and the data bus is 16-bits for the 8086 and 8-bits for the 8088.The data bus in the 8086 is 16 bits in size, while the address bus is 20.
8086 has 20 address lines. Therefore it can address 220 bits or 1,048,576 bits of memory, or roughly 1 MB (mega byte).
The 8086/8088 has 20 address lines. It can access 220, or 1MB, or 1,048,576 bytes of memory.
The highest memory address in the 8086/8088 is FFFFFH.
128Kb
displacement from base address
In the 8086 microprocessor, the ALE (Address Latch Enable) pin is used to synchronize slow peripherals. This pin indicates that the address bus contains a valid address, allowing slower devices to latch the address for data transfer operations. By using ALE, the 8086 ensures proper timing and coordination with external components, facilitating effective communication with peripherals.
In the 8086 microprocessor, reading word-sized data is generally faster from an even address than from an odd address. This is because the 8086 architecture is designed to access memory in 16-bit (word) chunks, and even addresses allow the processor to retrieve data more efficiently, aligning with its access patterns. When a word is at an odd address, the processor must perform an additional cycle to fetch the data, resulting in slower access times.
You cannot address 1GB memory with the 8085 or the 8086/8088 without some kind of external demultiplexor that is software controlled. The address bus on the 8085 is 16 bits, giving addressibility of 64KB; while the address bus on the 8086/8088 is 20 bits, giving addressibility of 1MB. To address 1GB, you need a 30 bit address bus.
The 8086/8088 has 20 address lines. It can access 220, or 1MB, or 1,048,576 bytes of memory.