You can determine your current firmware version by watching the screen on your MPX-500 during startup.
Install Instructions - Warning - Installing this chip backwards will damage the chip and your MPX-500!
1. Shut down your MPX-500 and disconnect power
2. Carefully open the cover of your MPX-500 to expose the circuit board.
3. Find chip "U9" as shown in the pictures. This is the chip you need to swap. Yours may look like the one in the picture or it may have a sticker on it. Be sure to note the orientation of the notch on the chip.
Recommended - Take a picture too, just in case you forget!
4. Pull the chip straight out with the chip puller tool ensuring not to bend any pins.
5. Install the new chip in the same slot ensuring you have the notch pointing in the same direction.
Note - You may need to carefully bend the chip legs slightly to align them with the socket holes.
6. Reinstall the cover, power up, and enjoy