In computing, a logical address is the address at which an item (memory cell, storage element, network host) appears to reside from the perspective of an executing application program.
A logical address may be different from the physical address due to the operation of an address translator or mapping function. Such mapping functions may be, in the case of a computer memory architecture, a memory management unit (MMU) between the CPU and the memory bus, or an address translation layer, e.g., the Data Link Layer, between the hardware and the internetworking protocols (Internet Protocol) in a computer networking system.
... Before discuss both types of address lets set some premises ... Physical address - the original address of each bytes of any memory device ... Logical address - A logical address is the address generated by CPU,which is easier to handle and programs assume that they resides at this address,but ...
... enhancements All registers are 16 bits wide Data address space expanded to 64 Kbytes First 2K is reserved for peripheral control registers Data bank switching is not required unless RAM exceeds 62K "f. 0 ... n 0 CALL addr23 Push PC, jump to absolute address —0— 0 ... n 1 ... — (Reserved) 0 ... n 0 GOTO ...
... In real mode each logical address points directly into physical memory location, every logical address consists of two 16 bit parts The segment part of ... a segments may start at physical address 0, 16, 32.. ... The offset part of the logical address contains an offset inside the segment, i.e ...
Famous quotes containing the words address and/or logical:
“The English, the plain English, of the politest address of a gentleman to a lady is, I am now, dear Madam, your humble servant: Pray be so good as to let me be your Lord and Master.”
—Samuel Richardson (16891761)
“The contention that a standing army and navy is the best security of peace is about as logical as the claim that the most peaceful citizen is he who goes about heavily armed. The experience of every-day life fully proves that the armed individual is invariably anxious to try his strength. The same is historically true of governments. Really peaceful countries do not waste life and energy in war preparations, with the result that peace is maintained.”
—Emma Goldman (18691940)