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Answered 2012-03-18 17:19:08

Memory mapped IO is one where the processor and the IO device share the same memory location(memory) while IO mapped IO is one where the processor and the IO device have different memory located to each other.

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Differeciate memory mapped io and io mapped io?

may mego kana

Explain Memory Mapped IO and IO mapped IO?

yes because when you see the telitobies you get a free ticket to watch barney and his friends its so awsme

What are the advantages of memory mapped IO?

Memory mapped IO uses a portion of RAM to handle IO requests. In this manner, instructions the CPU uses for reading and writing memory can also be used for IO, reducing the circuitry needed. This makes the CPU simpler, cheaper and more effecient.

What is the Difference between memory mapped IO and peripheral mapped IO?

A memory mapped IO device is an IO device that responds to a specific address when IO/M- is low. A peripheral (or IO) mapped IO device is an IO device that responds to a specific address when IO/M- is high.Many system designers ignore IO/M- in favor of memory mapped IO.This eliminates one term in the chip select logic for every device.This allows you to use all addressing modes and instructions when manipulating an IO device, as opposed to using only IN and OUT.This allows you to potentially have more than 256 different IO devices.The downside is that you reduce the addressable main memory in the system, i.e. you cannot have all 64K available to you, but this is not generally a problem in most controller designs. You also must decode 16 address lines instead of just 8 when accessing the device.

What is the Difference between memory mapped IO and IO mapped IO?

In memory mapped I/O, a chunk of the CPU's address space is reserved for accessing I/O devices. In I/O mapped I/O, I/O devices are handled distinctly by the CPU and hence occupy a separate chunk of addresses predetermined by the CPU for I/O. In case of Memory mapped I/O the same address BUS is used for accessing both Memory (RAM) and the Registers of I/O devices. For I/O Mapped I/O, separate address BUS is used. As Address space is generally larger for Memory than I/O registers, the length of I/O address is larger in case of Memory Mapped I/O. For a system which uses I/O Mapped I/O, there is a requirement for a extra h/w Circuitry.

What is Peripheral-Mapped IO?

Peripheral-Mapped IO is IO that is selected when the IO/M- line is high.

The maximum number of Io devices can be interfaced with 8085 in the Io mapped Io technique?


In 8085 microprocessor with memory mapped IO?

arithmetic and logic operation can directly perform with I/O data all i/o devices are treated as memory use 16 bit address

Block diagram of 8257 dma controller?

it is a device to transfer the data directly between io device and memory without through the cpu so it performs a high-speed data transfer between memory and io device

What is the function of IO in 8085?

IO/M- is used in the 8085 to qualify IO operations vs memory operations.

What is the difference between data and instruction in terms of fetching from memory?

In the 8085, instructions are data which become the program that the CPU executes. You can differentiate data from instructions by looking at S0, which is high for opcode fetch and low for data fetch. S1 is high in both cases and IO/M- is low in both cases.

If memory addresses are used by the CPU to access memory then what are io addresses used for?

To read and write to I/O

What are the four elements of a computer?

memory,cpu,io devices,monitor

How can you distinguish memory addresses from you IO port addresses?

Not possible, both are numbers.

What is the relation between Perseus and Io in Greek mythology?

Io is an ancestor to Perseus

Which bus transfers the memory address to the IO device or to the memory device?

DMA Direct Memory Access DMA transfers data directly from the drive to memory w/out involving the CPU.

What are the causes of bottleneck in your computer system?

The fundamentals of computer performance in terms of program execution always has three factors that influence performance 1. CPU 2. Memory and 3. IO (Input/Output) Any performance bottleneck will be related to one of these. To overcome the bottleneck you may need to increase the CPU capability if it is CPU bound, increase the memory if it is memory bound and remove the IO blocks if it is IO bound

What are the basic utilities of operating system?

1) To manage the memory 2) To manage the IO devices 3) To provide platform for interaction between computer & user 4) To mange the communication between devices & many more....

Which pin of 8086 is not compatible with 8085 for memory interfacing?

Pin 28 on the 8086/8088 is M/IO-, in minimum mode. The equivalent pin on the 8085 is IO/M-, and has opposite polarity.

What are the basic microcomputer elements?

A processor, memory, and some kind of IO (input/output) device(s).

What is the distance between IO and Europa?

justin bieber

What are memory read memory write IO read IO write operation in concept of microprocessor 8085 give the detail explanation?

Each data transfer is 3 clock cycles. The first cycle emits address and status, and ALE is used to strobe the low order address. Status is S0, S1, and IO/M- The second cycle sets up the transfer, either floating the data bus for a read, or drving the data bus for a write, and then initiating transfer with RD- or WR-. If READY is not true at the sample point (about the middle of the second cycle) an extra cycle is appended after the second cycle, with all lines frozen, until READY goes true. The third cycle wraps up the transfer. The processor samples data one half cycle before the end of RD- for a read, and it holds the data bus valid for one half cycle after WR- for a write. Up to this point, all cycles are similar. What matters is IO/M-. If high, this is an IO read or IO write; if low, this is a memory read or memory write. However, you have to consider S0 and S1. These are advanced status pins, along with IO/M-, that indicate what the processor is doing. They are emitted at ALE. In addition to indicating IO Read, IO Write, Memory Read, and Memory Write, you can decode Opcode Fetch, Interrupt Acknowledge, and Halt.

How a 8085 differentiate data and instruction?

The 8085 (sort of) differentiates between data and instructions with the S0 and S1 status pins. Considering IO/M- to be low (memory only), S0 is high on opcode fetch and memory write, and low on memory read, while S1 is high on operand fetch and memory read, and low on memory write. (You need to decode them to see a clear picture.)However, on a multiple byte instruction, S0 is high only on the first byte, and it is low on subsequent bytes, so it is a bit more difficult to tell the difference. If you really needed to know, you would need to track the memory cycles starting with opcode fetch, knowing the opcode meanings, and noting the immediate instruction bytes as opposed to anything else.

What is the distance between Io and the earth in AU's?

100000km \ by 100mm

What are simalrity between Io and Luna?

They are very similar in size