I selected COM6 250000 and I get this error message “ValueError: Cannot configure port, some setting was wrong. I have loaded and started Pronterface, plugged in the power supply to RAMPs (USB connected). With RAMPS shield on, no power plugged into the ramps shield, Windows sees RAMPS (COM6). Yes, Windows sees “RAMPS (COM6)” without the shield connected. Has anyone seen this, and is there a way to fix it? I did a visual inspection of the Mega, top and bottom, and I don’t see any bad solder joints or any other visual damage. If I press reset, I will get some gibberish in the serial monitor (like when the Baud Speed is set wrong). The error I get from the Serial Monitor of the IDE is “Error while setting serial port parameters: 250,000 N 8 1”. The two red LEDs labeled L and ON both light steady. When I connect the Mega (from the Parts Bundle) to the USB, it’s recognized by Windows, and it has a port number. The RAMPS Board is good, so it must be the MEGA. I can control all three X, Y, and Z axes. I can connect to the Arduino IDE Serial Monitor, and I can connect to Repetier. I have another Mega not being used right now, so I loaded the RAMPS-RC firmware downloaded from the link in the Assemblies page. I can’t get a serial connection to the Mega from the Arduino IDE, and I can’t connect to Repetier.

I tested the RAMPS/Mega board by connecting 3 stepper motors, resistor and pugging in the power supply. My parts bundle arrived yesterday! While my parts are printing, I am doing other things in preparation for the build.

Ramps 1.4 usb 2.0 serial driver