Memory addresses
Up until this point, we have explored the types of memory and memory devices. However, what we have not explored is how memory works. As such, this section is going to be dedicated to exploring how memory works.
How memory works
Conceptually, memory can be visually represented by Figure 4.1:
Figure 4.1 – Computer memory representation
Computer memory can best be thought of as tiny sections that compose the overall memory system. In the case of Figure 4.1, each memory square is a memory block. That is, each square will hold a piece of data such as the number of parts to make or the state of the machine.
Each memory block has an address that is used by the PLC to organize and keep track of the memory locations. In the case of Figure 4.1, the address is the alphanumeric label in the diagram. When data needs to be retrieved, the computer or PLC will invoke the memory address and retrieve the value. On the flip side of that...