Content deleted Content added
low-pin-count w/hyphens like at https://www.eetimes.com/flash-storage-alternatives-for-the-low-pin-count-lpc-bus/?_ga |
No edit summary Tags: Visual edit Mobile edit Mobile web edit |
||
Line 3:
{{Computer architecture bit widths}}
'''4-bit computing''' is the use of [[computer architecture]]s in which [[integer (computer science)|integers]] and other [[data (computer science)|data]] units are 4 [[bit]]s wide. 4-bit [[central processing unit]] (CPU) and [[arithmetic logic unit]] (ALU) architectures are those that are based on [[processor register|registers]] or [[Bus (computing)|data buses]] of that size. A group of four bits is also called a [[nibble]] and has 2<sup>4</sup> = 16 possible values, with a limit of -8 to 7.
4-bit processors were widely used in [[electronic calculator]]s and other roles where decimal math was used, like electronic [[cash register]]s, [[microwave oven]] timers, and so forth. This is because a 4-bit value holds a single [[binary coded decimal]] (BCD) digit, making it a natural size for directly processing decimal values. As a 4-bit value is generally too small to hold a [[memory address]] for real-world programs or data, the [[address bus]] of these systems was generally larger. For instance, the canonical 4-bit [[microprocessor]], the [[Intel 4004]], had a 12-bit address format.
| |||