Subroutine I/O involves the CPU executing a series of instructions to perform input/output operations, where the CPU is actively involved in managing the data transfer. In contrast, interrupt I/O allows the CPU to continue executing other tasks while peripheral devices signal the CPU when they are ready for data transfer, thereby improving efficiency and responsiveness. Interrupts can preempt the current execution flow, allowing for asynchronous handling of I/O operations, while subroutines require the CPU to be dedicated to the I/O task until it completes.
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.
Here are the prime numbers between 10 and 30: 11, 13, 17, 19, 23, 29 Prime numbers are those numbers which cannot be divided to give an integer result except when divided by themselves or by 1.
1.Programmed IO is the process of IO instruction written in computer program , where Interrupt Initiated IO is done by using interrupt and some special command. 2.The advantage of Interrupt Initiated IO is ,it is a time consuming process than Programmed IO. 3.In Programmed IO technique to transfer data,required constant motoring on peripheral by CPU,once data transfer is initiated, CPU have to wait for next transfer. In Interrupt Initiated IO once data transfer initiated ,CPU execute next program without wasting time and the interface keep monitoring the device. When the interface determines that the device is ready to transfer data, it generate an interrupt request,CPU stop the current task,execute the transferring process,and then return to the previous on-processing task.
disadvantages of interrupt
il means the and io means I
Io is an ancestor to Perseus
If a process requests that the O/S write data to disk, and has to wait for it to be written before continuing, then that is Synchronous. If the process does not have to wait for the write to be completed, that is Asynchronous. Synchronous is real-time.
Maybe you have seen something called an interrupt as you work on your computer. These Interrupt Requests come from processes or devices that want to use resources. It's all very orderly.
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.
Blocking IO: The program will pause and wait until the IO operation is complete before resuming. This technique can lead to inefficiency if there are multiple IO operations. Non-blocking IO: The program continues to run while waiting for the IO operation to complete. This allows for better efficiency when handling multiple IO operations simultaneously. Asynchronous IO: The program initiates the IO operation and continues executing, without waiting for the operation to complete. A callback function is usually provided to handle the result once it is available. This allows for better performance in handling large numbers of IO operations.
Polling checks constantly the status of de I/O device, wasting CPU cycles. However with Interrupt driven I/O the device sends a request to the CPU to indicate that it needs attention. So, in some cases, Interrupt driven I/O will be better than polling, because doesn't waste CPU cycles checking when the device needs attention.
justin bieber
multiprogramming-there is no way for single user to keep either cpu or the io divices busy at all times...
Io orbits Jupiter at a distance of 421,700 kilometres. Which si about 10% further than the Moon is from Earth.