Reading and Writing Memory

The processor can do two fundamental things with main memory:

1. It can write a bit pattern to a byte at a given memory location.
   • The previous bit pattern in that location will be destroyed.
   • The new bit pattern is now saved for future use.
2. It can read a bit pattern from a byte from a given location.
   • The processor gets the bit pattern stored at that location.
   • The contents of that location are NOT changed.

For example, if the processor needs to get the byte stored at location 5, it can read it. It gets 0110 1110 as the data it needs (but location 5 in memory does not change.)

Most processors can write (and read) more than a single byte at a time. This speeds things up. But the two operations above are fundamental.