Circuit Initialization Before Running

Discussion in 'Digital Circuit Design' started by PauloConstantino, Oct 16, 2016.

  1. PauloConstantino

    Thread Starter Member

    Jun 23, 2016
    Hi Everyone,

    if some of my elements in my architecture need to be initialized to certain values before the machine actually runs the algorithm, does this mean that I should have a set of initializing states in my state machine?

    In general, when a system needs some elements to be initialzied to certain values, does the state machine usually have these initializing states before the main algorithm runs?

    Let's say for example in the old SNES video game console, where you would move the START switch to the ON position for the console to start reading the game cartridges etc.

    Is the SNES going through the initializing states as soon as the START is moved to the ON position, and then after this the algorithm starts running?

    Please Look at the diagram I attached here to see what I mean....

  2. WBahn


    Mar 31, 2012
    How you deal with initialization depends on a number of factors. One common way is to have a reset input that causes the system to initialize and then you have a POR (power-on reset) circuit that is nothing more than an RC filter that hold the reset asserted for some amount of time after power comes up -- long enough for the supplies to settle and all the transients to die out.

    How you go about performing the initialization is another question with lots of viable answers depending on what kind of initialization needs to be done and what the resources are to make it happen. If you have a microcontroller or other programmable logic you often have the reset input start a state machine (or part of the program) that performs the initialization before turning control over to the main part of the system.