How many data lines and address lines does the 8086cpu have?

8086cpu has 16 data lines and 20 address lines. It can process both 16-bit data and 8-bit data. The addressable memory space is 1MB; because 8086cpu has an available 20-bit address, it can The addressed address space is 220 bytes or 1MB. The 8086cpu is a microprocessor launched by INTEL in June 1978, clocked at 4.77MHz, using 16-bit registers, 16-bit data bus and 29,000 3-micron technology transistors.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

The 8086 CPU is a microprocessor launched by INTEL in June 1978, clocked at 4.77MHz, using 16-bit registers, 16-bit data bus and 29,000 3-micron technology transistors, marking the third generation The microprocessor is introduced.

The 8086 is available in three clock frequency versions: 4.77, 8 and 10MHz, including an instruction set with 300 operations. The 8MHz version contains approximately 28,000 transistors and has a capability of 0.8 MIPs.

8086cpu has 16 data lines and 20 address lines. It can process both 16-bit data and 8-bit data. The addressable memory space is 1MB. External data bus width: 8086: 16 bits; 8088: 8 bits. The internal data bus width is the same, 16 bits. The address bus number of Intel's 80286 processor has been increased to 24 bits, so 16M of memory space can be accessed. What's more important is that a new concept, protection mode, has been introduced since then. Access to memory segments is restricted in this mode.

Because there are 20-bit addresses available, the addressable address space reaches 220 bytes or 1MB. Almost at the same time as the 8086 microprocessor was launched, in order to be directly compatible with the existing set of Intel peripheral interface chips at the time, the quasi-16-bit microprocessor 8088 was also launched. The internal registers, internal arithmetic components and internal operations of the 8088 are all 16 bits, but the external data bus is only 8 bits.

The instruction queue of 8086 is 6 bytes. While the CPU is executing instructions, it takes one or several instructions from the memory and places them in the instruction queue. In this way, under normal circumstances, the 8086 can execute an instruction immediately after executing it, instead of taking turns to fetch and execute instructions like previous computers, thus improving the efficiency of the CPU. The address adder is used to generate the 20-bit address. The 8086 can address 1MB of memory space with a 20-bit address, but the internal registers of the 8086 are all 16-bit, so an additional mechanism is needed to calculate the 20-bit physical address based on the information provided by the 16-bit register. This mechanism is the 20-bit address. Adder.

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