Beginner looking for help - RAMPS issue?

I am new to both reprap and Arduino, but thought prehaps a kit might be an interesting project for my high school robotics class. We bought a makerbot mendel prusa kit and have finished most of the construction. My problem is apparently the RAMPS 1.4.
I have been over the board a few times. I am trying to compile and load the blink and fade sketches that are included with the Arduino software to start communicating with the ArduinoMega2650. Without the RAMPS in place it works as it should. Once I install the shield, the arduino hangs during the upload and I get timeout errors. (avrdude: stk500v2 ReceivedMessage(): timeout) I am assuming I should still be able to upload these sketches with the RAMPS installed???
Needless to say I cannot upload the firmware(trying to load Marlin) as it also hangs with Timeout errors.
It has been a while, but my soldering skills are adequate for the RAMPS.
Think the next step might be to try a fully built and tested shield. Should I stick to RAMPS or try something else?
Suggestions? Many thanks.

running Win XP, but also hangs at the same spot on a mac laptop.

Perhaps the shield is drawing too much power and causing the voltage regulator to shut down during the download?

Have you tried it without the stepper drivers installed?

What happens if you upload without the shield and then run it with it attached?

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Have you powered up the ramps board with a 12V source? If you have the D1 diode installed, the arduino should power up also.

Quote: "D1 should only be installed if the 5A rail is powered by 12V. It can be omitted and the Arduino will be powered from USB. You will want D1 installed if you add components to print without a PC. To reiterate, D1 MUST be omitted if you are powering the 5A rail by more than 12V."

The arduino mega can apparently handle 20V through it's voltage regulator circuit, If you are using more than 20V you have to remove the D1 diode and power the arduino through USB.

I do not believe I have the diode installed. The RAMPS board I got in the Makerbot kit is slightly different than most I have seen. It was partially finished with surface mounted components. I have attached a photo of my finished board. I see D2 labeled and installed. Where would D1 go?. It could well be a power issue. Both 12volt inputs are connected and drawn from the ATX power supply they included.

I have ordered a tested RAMPS board that I can use for testing my setup
My RAMPS circuit board RAMPS

nophead,
Thanks for your interest. Yes, I could upload the Marlin firmware without the shield in place. One of my students then attempted to test using a test sketch for the printer. I only have the x axis motor connected to a single pololu motor driver, since I did not want to test all the motor controllers at once. I was hoping the the sketch would move each of the steppers in turn so that I could see some movement on the x axis. Nothing happened. This was with both 12volt connectors attached and providing power from the atx power supply (but apparently without the D1 diode installed) Any ideas?

here it is.

Try testing for resistance from the +12 and Gnd (with the power disconnected) to see if there are any shorts.

D1 is installed under the y axis motor controller. Hard to tell, if polarity is correct. Cathode band is toward power connectors. And, yes, it was the y axis motor I was hoping would move during the test sketch.

are the polulus installed in the proper direction? if you hold the board so that you can read the words, the pots should be on the right.

on 11 amp side no short
on 5A side it reads about 800 ohms between + and -

yes, they are properly oriented, but pots have not been adjusted as of yet. Also attaching a scan of the bottom of the RAMPS

Does it still short out without any polulus connected?

Thanks to all. I purchased a tested RAMPS 1.4 board from Ultimachine since I did not trust my soldering skills. Installed the new RAMPS but still had issues. Discovered a problem uploading sketches from our PC, but found we could do so from a MacBookPro. Compiled and uploaded the test sketch from this site and now can get the motors moving. Here are my latest questions:

the makerbot kit included only three mechanical endstops. Do I not need six? Advantages/Disadvantages of six?
Do I upload the Marlin firmware just as any other sketch using the Arduino app?
Under Arduino app "Tools" I can set the Board to Mega2560 and port. What setting for programmer?
I ordered a cheap 4X20 LCD from China on ebay. What mods to hardware/software are required?

Again, thanks to all. I am in Naples, Florida and looking for anyone local with some expertise.

You need any endstops really, but the 3 you have should be used for homing the machine. Using another 3 will allow you to set limits on the size of object that can be built (because of the size of the machine)

Yes you upload marlin the same way you would any other sketch. Just make sure you modify configuration.h beforehand.\

Board and port are the only things you need to set to program the arduino mega.

Pronterface gives you all the info you need, I don't see a need for an LCD.

I had the same issue with being able to upload the Firmware/blink when the ramps board was not connected. But not when the board was connected. My board was a preassembled ramps 1.4

What version of Arduino are you using? What I found thanks to the forums was that using Arduino 0.22 I could upload when the ramps 1.4 was connected, but with Arduino v 1.0 I could not. I now use the earlier version for all my uploads.

Thanks, will give it a try.

I too have noticed the problem when trying to upload a sketch with the Arduino v1.0.1 if the RAMPS 1.4 board is attached. The Mega programs fine with it removed. Anyone have a solution to this?

Most of us are using the 0.23 Arduino release rather than the 1.01, but I doubt it matters.

The OP's issue was probably power, All Mac's can provide well over the minimum USB power requirements I believe they are rated for 1100mA on the USB 5V line so they can charge IPads.
The standard only requires 500mA (900 for USB3 I think) which should be plenty, however there are other restrictions, most buses only support a single high powered USB device, and the remaining ports will only output 100mA if one is connected.

If this is your problem and it could be any number of things.

If you have D1 installed and external power it shouldn't matter.

I would try un-plugging any USB peripherals on the driving PC that are not essential.
Failing that try a powered USB hub.

Polygonhell Wrote:
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> Most of us are using the 0.23 Arduino release
> rather than the 1.01, but I doubt it matters.

It does on some firmwares, but if that was the problem I'd expect failure to compile, not failure to upload.