Differences between Isolated I/O and Memory mapped I/O - 8086
List out the differences between Isolated I/O and Memory mapped I/O.
The characteristics of isolated I/O are as follows:
- The devices of I/O are treated in a separate domain as compared to memory.
- A total of 1mb address space is allowed for memory applications.
- In order to maximize the I/O operations ( isolated ) separate instructions are always provided to perform these operations.
- One of the disadvantages is that the data transfer only occurs between the I/O port and the AL, AX registers.
The characteristics of the memory mapped I/O are as follows:
- In such scenarios the devices (I/O) are treated as a part of the memory only.
- Complete 1mb of memory cannot be used as they are a part of the memory.
- In case of memory mapped I/O operations no external separate instructions are required.
- There is data transfer restriction in case of memory mapped instructions.