Download Logisim, I recommend Logisim-ITA or Logisim-EVO. Except you'll have to edit the circuit a bit in Logisim Evolution because of how it is. You will also download my .circ file and import it into Logisim.

Download the .circ file and import it into Logisim.

Download MARS, a MIPS assembler, which is a pretty awesome piece of software if you ask me.

Open your .asm file in MARS, save your file, then click the "Assemble" button. You'll be brought to a new page in MARS, and you can click the "Run Program" green play button to simulate your .asm file.

*NOTE* Please read the updated supported instructions list. I'll be adding different instructions when I have the time.

Click the "Dump File" button after you've assembled and ran your program and made sure it works.

You will be asked what format you want it in, and click "Hexadecimal" , and name it whatever you'd like. with a .txt at the end. like "mips.txt"

You should be able to open it, and just select all of the contents and copy them.

Go into Logisim, and right click on the "Instruction ROM" subcircuit, then click "View INSTRUCTION MEMORY" *NOTE* You have to click "View INSTRUCTION MEMORY" in order to have it work. I know, it's weird.

Right click on the ROM, and hit "Edit Contents" then paste the contents of you mips.txt file into it. NOT the mips.txt file itself. Just the hexadecimal contents.

Once you've put your HEX into the ROM, you can go to  "Simulate" and click "Ticks Enabled"

To select your speed, go to "Simulate" hover over "Tick Frequency" and click your desired speed.