The Marsa33 firmware can run simulated flight to about 3300ft to test the event programming.  During the simulation the altitude is displayed on the LCD and you can observe the output channel LED's to confirm the programmed events are happening according to the program you intended.

To put the altimeter in Simulation mode and run the simulated flight:

1. Starting with the Marsa33 powered off
2. Hold the joystick to the left
3. Apply power to the Marsa33

The Marsa will emit a long beep and the LCD display will warn that the altimeter is in simulation mode.

The Marsa will stay in simulation mode until the simulated flight completes and all the programmed events occur.