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Gabriel15's avatar
Gabriel15
Icon for New Contributor rankNew Contributor
6 months ago

How to fix State <name> contains multiple transitions, but more than one transition equation are TRU

I'm trying to develop a Elevator FSM machine in quartus in order to get his equivalent to HDL code. The FSM is this:


But when I set the Input, transitions and output in "State Machine Wizard", it return me the following error message

Error (154039): State S1 contains multiple transitions, but more than one transition equation are TRUE when ~R2 & R1 & R3 | R2 & ~R1 & R3 | R2 & R1. As a result, the next state cannot be decided.

Error (154039): State S2 contains multiple transitions, but more than one transition equation are TRUE when ~R2 & R3 & R1 | R2 & ~R3 & R1 | R2 & R3. As a result, the next state cannot be decided.

Error (154039): State S3 contains multiple transitions, but more than one transition equation are TRUE when ~R3 & R2 & R1 | R3 & ~R2 & R1 | R3 & R2. As a result, the next state cannot be decided.

This is how I set the inputs:

The Outputs:


Transition:

Actions:


If anyone can help me to approach the expected solution, I'd be really grateful.

Hdl

6 Replies

  • sstrell's avatar
    sstrell
    Icon for Super Contributor rankSuper Contributor
    5 months ago

    Tip: learn to code in HDL (Verilog or VHDL) instead of relying on the State Machine Editor/Wizard. You'll learn a lot more.

    But regarding your design, can you show the code generated by the tool? Are these supposed to be 2-bit wide inputs and 3-bit wide outputs, or is that just how they are represented numerically in the tiny diagram you've attached?

    Also, you're setting output ports to the input ports? Output Value is usually a value (a number).

    Show the code output from the SME. That will make it much easier to understand what you've done here.

  • KennyT_altera's avatar
    KennyT_altera
    Icon for Super Contributor rankSuper Contributor
    5 months ago

    Sorry for the late reply on this, not sure if you have update of your code? Like previously mention, it will be easier to understand once you provide the code to us.


  • RichardT_altera's avatar
    RichardT_altera
    Icon for Super Contributor rankSuper Contributor
    5 months ago

    Sorry for the delay.

    Do you need any further assistance regarding this case?

    I agree with sstrell—using HDL language for FSM design is a better approach for implementing state machines.

    Attached is an example code based on your elevator scenario.

    Let me know if it works for you.

    Regards,

    Richard Tan

  • RichardT_altera's avatar
    RichardT_altera
    Icon for Super Contributor rankSuper Contributor
    4 months ago

    We noticed that we haven't received a response from you regarding the latest previous question/reply/answer, and will now transitioning your inquiry to our community support. We apologize for any inconvenience this may cause and we appreciate your understanding.

    If you have any further questions or concerns, please don't hesitate to reach out. Please login to https://supporttickets.intel.com/s/?language=en_US, view details of the desire request, and post a feed/response within the next 15 days to allow me to continue to support you. After 15 days, this thread will be transitioned to community support. The community users will be able to help you on your follow-up questions.

    The community users will be able to help you on your follow-up questions.

    Thank you for reaching out to us!

    Best Regards,

    Richard Tan