Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
I don't really understand "I/O mapped memory"
1) There is internal memory and external memory. Simply memory can be inside the IC or in another external IC.
2)There is CODE memory which can be read but not written and normally contains instructions. AND Data memory (RAM memory) that normally holds data.
That describes 4 types of memory.
If we are talking about the intel..... Then mapped I/O refers to address space..... I'll explain...
On most micro controllers ports, modules and peripherals are set in stone... Each has several address in memory SFR's ( RAM) that controls their actions.. The Intel micro also has SFR's for the basic stuff.. BUT! can also have mapped I/O... If you place an LCD at some arbitrary address.. ie.. 0xA000... You can read and write to that address, the same as you would if it were an SFR...
By memory mapped I/O, are we referring to the ability to use hardware buffers and gates to hard lock a piece of hardware interfaced to the 8051's FSB to a RAM memory address or address block, then read/write on that piece of hardware via use of the movx instruction?