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The data bus in the 8086 is 16 bits in size, while the address bus is 20 (16bits would only address 64KB of memory, an extra 4 bits allows to address the total of 1MB, this is done trough segmentation of the memory).
To form a multiplexed of data bus and address bus, four bits of 8086 address bus are grounded.
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How multiplixed data and address bus of 8086 can be de-multiplixed?
The 8086 has a 20 bit address bus and a 16 bit data bus. The low order 16 bits of the address bus share the same 16 pins as the data bus. The low order 16 bits of the address are emitted in the first clock cycle of a memory access cycle. External logic is expected to latch that address. Then the bus becomes a data bus. The high order 4 bits of the address bus are handled separately.The determination of operand size (8 bit vs 16 bit) is made by BHE and A0. If BHE is high, it is a 16 bit operand at an even address. If BHE is low and A0 is low, it is an 8 bit operand at an even address. If BHE is low and A0 is high, it is an 8 bit operand at an odd address.
If a memory had 16 bit address bus and a 32 bit data bus what is the largest size of the memory?
A memory with a 16 bit address bus can address 216 or 65536 distinct items. If each item is 32 bits in size, then the item is 4 bytes. The size of this memory is then 262144 bytes. (256Kb)
How much memory can be address with 32 bit address bus?
32 bit address bus can access more than 4 gigabytes (232) of memory. Sandeep Kr. Singh (MCA)
How many bytes of date can be addressed by a computer system with an 11-bit address bus and an 8-bit data bus?
There can be one byte of data transferred at one time on the 8-bit data bus, but without knowing more about the architecture and the address and data bus multiplexing we cannot know how many bytes can be addressed.Perhaps the machine architecture uses 2 address bus cycles to send out a 16-bit address and 6-bits of control signals, then uses 2 data bus cycles to read or write the 16-bit word at that address, which would mean this computer system addressed two bytes at one time.Perhaps the machine architecture uses 3 address bus cycles to send out a 32-bit address and a 1-bit control signal, then uses 4 data bus cycles to read or write the 32-bit word at that address, which would mean this computer system addressed four bytes at one time.Perhaps the machine architecture uses 6 address bus cycles to send out a 64-bit address and 2-bits of control signals, then uses 8 data bus cycles to read or write the 64-bit word at that address, which would mean this computer system addressed eight bytes at one time.Perhaps the machine architecture has a variable word length (which could be specified in many different ways depending on the architecture), in which case almost any number of bytes could be addressed at one time (with different numbers of bytes in each addressing operation).There are many other possibilities.
Was atari 2600 4 bit?
No, there were no 4-bit consoles. The 2600 uses the 8-bit 6507 CPU and an 8-bit bus.
What is the purpose of an address bus?
The address bus is used by the processor in a computer to locate a piece of data from the RAM (Random Access Memory) that it needs to access. No real data is carried via the address bus, as this is the job of the Data Bus. The pieces of data that the address bus locates are called "addresses" and the address bus transfers "data addresses" to and from the control unit.
How many times can a 32 bit bus can handle versus the data bits as an 8 bit bus?
Assuming the raw bus speed is the same, you should be able to move 4 times as much data across a 32-bit bus as across an 8-bit bus, because there are 4 times as many bits. It's never that simple, though. The 8-bit bus on the original IBM PC was a 1.3MHz bus, and so could move about 1,300,000 bytes per second, flat out. The 32-bit bus specified by the VESA consortium for the 486 was a 33MHz bus and so could move 133,000,000 bytes per second, flat out. The multiplier in this case as closer to 100x.
What is meant by multiplexed address data bus?
Multiplexing of the data and address buses is done to reduce the pin count on the microprocessor chip. The address information is emitted at the beginning of a memory cycle, and external logic is expected to latch that address. Then the bus becomes the data bus and the required data is transferred to or from memory using the latched address.In the 8085, this saves 8 pins at the cost of 1 pin, ALE. In the 8086/8088, this saves 16 pins at the cost of 1 pin, ALE. In some architectures or modes, there is no ALE, but the external logic is still required to know when to latch the address based on some other criteria.As an example of that, in the original Intel 4004, the microprocessor's bus was 4 bits, while the address bus was 12 bits. There were 8 clock cycles. In the first three, external logic was expected to latch the three 4 bit parts of the 12 bit address. Similarly, in the next two, the resultant opcode, which as 8 bits, was multiplexed by the external logic into two 4 bit parts. (The 4004 was only a 16 pin chip, but it packed a lot of complexity in its day, being the world's first microprocessor.)
Difference between 80186 and 80286 and 80386?
5/2/2012 Laith fahim from Iraq,Baghdad 80386 (or 80386DX) is internally and externally a 32-bit microprocessor with a 32-bit address bus. It is capable of handling physical memory of up to 4 GB (232).Virtual memory was increased to 64 terabytes (246) . 80386SX has a 16-external data bus and a 24-bit address bus which gives a 16MB (224) of memory . that is makes more cheaper from the 80386DX _________________________________________ the 8086 IBM PC and compatible computer 4ht edition by Mukammad Ali & Janice Gillispie
What is the typical bus width of an Intel Pentium 4?
32 bit is the default.
What is the difference between the Intel 8085 and the Intel 8086?
The Intel 8085 is an 8 bit microprocessor created in 1977.The Intel 8086 is a 16 bit microprocessor created in 1978. The 8086 was the first chip to start the x86 architecture family.8085 contains 16-bit address bus and 8-bit data bus8086 contains 20-bit address bus and 16-bit data bus..In 8085 the clock speed is 3MHZwhere as in 8086 the clock speed is 5MHZ.there are two differences btw 8085&80861. 8086 has 6 byte queue but 8085 has 4 byte queue2. 8086 has 16 bit data bus where as 8085 has 8 bit data bus
Why program counter and stack pointer is 16- bit?
Because that's how Intel designed it. Even though the 8085 is an 8-bit computer, the program counter and stack pointer are 16 bits wide in order to support the address bus, which is also 16 bits wide. In the case of the 8086/8088, the program counter and stack pointer are still 16 bits wide, even though the address bus is 20 bits wide, because the 8086/8088 adds segmentation through the 16 bit segment register which is left shifted by 4.
