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Todd123's avatar
Todd123
Icon for New Contributor rankNew Contributor
1 year ago

Help with Max10M08 doing a simple task

Hello, complete novice here with FPGA in general. I have 10M08SAE144C8G evaluation kit and I am trying to program something really simple, but the outcome is not what I expect.

What I have in Quartus is an input (PIN 90) that goes to both inputs of a NAND gate, so I can invert the Output (PIN 91). The input voltage is 3V and I also tried 2.5V, however the output is really distorted. Tried setting the input PIN 90 as a 2.5V Schmitt Trigger in the I/O Standard and the same for the Output PIN 91, however when I use the scope to check the output, I just get garbage.

As a complete novice I have only connected the USB to my MAX10 board and also have a common ground between the board and the 2/5V (or 3V) power source that I am using for the Input signal. Also tried using input clock signal with square waves and the output is always analog signal garbage. Anything else that I should be connecting to my board that I might be missing? The code in Quartus should not be the problem (unless if I am picking the wrong PINs for some reason that I don't understand yet).

Any thoughts on how to get this in order?

N.B. for my power source signal I use 5V with a voltage divider to take it down to 2.5V (or 3V). Also programming the board seems to complete without any issues and when I tested a few times, once I actually got somewhat correct results and it started showing garbage again shortly after.

If possible to advice on what PIN should I connect external Clock signal as I already have build a VGA sync program, however I won't work as I expected, so I decided to start with something really simple, before I get ahead of myself.

Board Debug
Configuration
Generic Io
Power

3 Replies

  • FvM's avatar
    FvM
    Icon for Super Contributor rankSuper Contributor
    1 year ago

    Hi,
    I would use on-board 50 MHz clock source for tests. If you need different clock frequency for a specific purpose, e.g. VGA controller, try to generate it with internal PLL. An external clock source can easily produce ringing edges or even overshoot outside maximum voltage ratings. For visualisation of simple logic, I'd refer to on-board switches and LEDs in the first place.

    Don't know what you consider as "analog garbage" in your tests? How did you connect oscilloscope probes to the board?

    Regards
    Frank

    • Todd123's avatar
      Todd123
      Icon for New Contributor rankNew Contributor
      1 year ago

      Thank you for the advice on using the internal clock. Already checked a few videos on how to use the internal PLL and it seems easy enough to set, so I will try it as soon as I can.

      Sorry about the "analog garbage" term. What I meant is that I expected a clean Output since it has a Schmitt Tigger that it's going through, but instead it has all kind of noise in the signal and the frequency is all wrong as well. Most probably it's due to the ringing edges that you mentioned and it's messing up the whole thing.

      As for the oscilloscope probe I had it connected to the common ground and the Output pin to check the voltage and frequency when I was testing the VGA H and V sync signals.

      Warm regards,
      Todor P.

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    1 year ago

    Hi Todor,


    Are there any updates you would like to share with us?

    Does it help you to solve the issue?


    Regards.

    Aqid