In the schematic that you show you appear to have edited the symbol for a current source and turned it into the symbol for a buzzer or a loudspeaker. It is not clear why you have done this because the simplest way to represent a buzzer or loudspeaker - without going into some very complex simulation techniques to represent loudspeaker back emfs and microphonic effects - is as a resistor such as in RSPKR in this simulation: [https://easyeda.com/editor#mode=sim,id=7975219d29684700820e33bf631e060d](https://easyeda.com/editor#mode=sim,id=7975219d29684700820e33bf631e060d)<br> <br> You simulation will not run as expected if at all because you have: 1. used a mix of schematic and spice symbols and; 2. changed the name of to 555\_BJT\_EE spice symbol so that it will not call the 555\_BJT\_EE spice model\. Note also that you also appear to have left pin 4 of U1 pulled low so U1 is permanently in the reset condition. Before asking for further help for simulations in EasyEDA please make sure that you have carefully read and played with the examples in the Simulation Tutorial, (3) in Welcome to EasyEDA, (2) in: [https://easyeda.com/forum/topic/How-to-ask-for-help-and-get-an-answer-71b17a40d15442349eaecbfae083e46a](https://easyeda.com/forum/topic/How-to-ask-for-help-and-get-an-answer-71b17a40d15442349eaecbfae083e46a)<br> <br>

Please also change the Category of this topic to Spice Simulation.

Thank you for the tip, I did as you told me and it worked properly, I also finished my circuit but there's last error. Please check what's causing this. Thank you! Sorry just a noob... <br> <br>  

"...I did as you told me and it worked properly..." No you didn't and no it doesn't. <br> Open: [https://easyeda.com/forum/topic/How-to-ask-for-help-and-get-an-answer-71b17a40d15442349eaecbfae083e46a](https://easyeda.com/forum/topic/How-to-ask-for-help-and-get-an-answer-71b17a40d15442349eaecbfae083e46a)<br> <br> which tells you to:  where link number 3 says:  and the introduction to that document says:  and: 

@andyfierman Yes, directing me to the document. I did read it but still doesn't quite understand as I am really new to this one... So your help would really be appreciated. I hope you could tell me which part of the connection is the mistake.

" I did read it " What: all of [https://docs.easyeda.com/en/Simulation/Headings/index.html](https://docs.easyeda.com/en/Simulation/Headings/index.html)<br> <br> including the section that describes where to find simulatable components unlike those such as U1 and, I suspect, the pots, that you have placed in your schematic? If you have made your project public so that others can study it and maybe offer suggestions then please post the url to it here.

@andyfierman I did use spice model in my 555 timer. And now I changed the pots with the ones from the spice. It says now that the cpu cannot handle the circuit.

"If you have made your project public so that others can study it and maybe offer suggestions then please post the url to it here."

Since you have failed to post the url to your public project or given a reason why you have not done so, I have taken the liberty of doing it for you: [https://easyeda.com/qjygsantos/final](https://easyeda.com/qjygsantos/final)<br> <br> and documenting the changes that you need to make to make it run. Now, for the final time of asking: read all of - and play with all of the examples in - the Simulation Tutorial. Then go back to your simulation and first do: **File > Export Netlist > LTSpice for this Sheet...** Download and study the netlist. Then: 1. Replace U2 with 555\_BJT\_EE from Spice Symbol library\. Do not edit the model name\! 2. Delete GND\_2 and GND\_3 netflags: the last placed symbol gives it's name to the net so your ground is named GND\_2 and not GND or 0V; 3. Delete U3.1 and U3.2 LM358N symbols from Schematic Symbol library; 4. Replace U3.1 with LM358_NS from Spice symbol library. These will place as U3; 5. Wire to connect; 6. Renumber as U3.1; 7. Select U3.1 and press "i"; 8. Edit the pin numbers to those of the originally placed U3.1. Do not edit the Spice pin numbers; 9. Copy and paste U3.1 into the original location of U4.1. This will place as U4.1; 10. Wire to connect; 11. Copy and paste U3.1 into the original location of U3.2. This will place as U5.1; 12. Wire to connect; 13. Renumber as U3.2; 14. Select U3.2 and press "i"; 15. Edit the pin numbers to those of the originally placed U3.2. Do not edit the Spice pin numbers. 16. Copy and paste U3.2 into the original location of U4.2. This will place as U5.1; 17. Wire to connect; 18. Renumber as U4.2; Now do: **File > Export Netlist > LTSpice for this Sheet...** Download and study the new netlist. Compare it with the original netlist. **Your simulation will now run.** Note that placing the interactive LEDs from the Commonly Used Library (was EELib) inhibits WaveForm display. You will learn more about how your circuit is operating if you delete these LEDs, replace them with DLEDR, DLEDG, DLEDY or DLEDO Spice Symbols from the Spice Symbol Library and then place Voltage Probes around your sim to see in the time domain what your circuit is doing. Note also that the prefix and pin renumbering of the LM358-N is so that it matches the pinout in your original design and so should still update the PCB OK though you may need to do Rests Component ID in both the schematic and the PCB first. So, I'm only giving you 3 out of 10 for your Final Project because you do not pay enough attention to information that you are given.