page_title: Algorithmic state machine
section_title: ASM chart
hierarchical_section_title: Algorithmic state machine / ASM chart
caption_attribution_description: English: A conditional output box used in ASM charts.
context_page_description: The algorithmic state machine method is a method for designing finite state machines originally developed by Thomas Osborne and Christopher Clare at Hewlett-Packard in the 1970s. It is used to represent diagrams of digital integrated circuits. The ASM diagram is like a state diagram but more structured and, thus, easier to understand. An ASM chart is a method of describing the sequential operations of a digital system.
context_section_description: An ASM chart consists of an interconnection of four types of basic elements: state name, state box, condition checks, and conditional outputs.  An ASM state, represented as a rectangle, corresponds to one state of a regular state diagram or finite state machine. The Moore type outputs are listed inside the box.
  State Name: The name of the state is indicated inside the circle and the circle is placed in the top left corner or the name is placed without the circle.
  State Box: The output of the state is indicated inside the rectangle box
  Decision Box: A diamond indicates that the stated condition/expression is to be tested and the exit path is to be chosen accordingly.  The condition expression contains one or more inputs to the FSM (Finite State Machine).  An ASM condition check, indicated by a diamond with one input and two outputs (for true and false), is used to conditionally transfer between two State Boxes, to another Decision Box, or to a Conditional Output Box.  The decision box contains the stated condition expression to be tested, the expression contains one or more inputs of the FSM.
  Conditional Output Box: An oval denotes the output signals that are of Mealy type.  These outputs depend not only on the state but also the inputs to the FSM.
caption: Conditional output box
exif: {}