11.2: Flip Flops
- Page ID
- 26884
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All memory cells located in the CPU are called registered, and are implemented as D flip flops. These flip flops are also called static ram, or SRAM. In this CPU, the values of the $ac and $pc, which store the current state of the CPU, are implemented as a group of 16 flip flops. These components are circled in red in Figure 11.1.1. Without flip flops, it would be impossible to maintain the state of the CPU, and the CPU could not do any useful work.
The number of registers in a CPU varies widely between the types of CPU, and even within a CPU itself. A more normal Accumulator CPU would have several more registers, such as a Memory Access Register ($mar), and a temporary register ($temp).