Hardwired OmniScriptum Hardwired Control: Computer, Central processing unit, Microprogramming, Microprocessor, Flip-chip, Digital Equipment Corporation

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. To execute instructions, a computer's processor must generate the control signals used to perform the processor's actions in the proper sequence. This sequence of actions can either be executed by another processor's software or in hardware. Hardware methods fall into two categories: the processor's hardware signals are generated either by hardwired control, in which the instruction bits directly generate the signals, or by microprogrammed control in which a dedicated microcontroller executes a microprogram to generate the signals. Before microprocessors, hardwired control usually was implemented using discrete components, flip-chips, or even rotating discs or drums. This can be generally done by two methods. The classical method of sequential circuit design. It attempts to minimize the amount of hardwire, in particular, by using only log2p flip flops to realize a p state circuit. An approach that uses one flip flop per state. While expensive in terms of flip flops, this method simplifies controller unit design and debugging.