Extruder drive problem

I am building a Prusa Mendel with Arduino Mega 1280 (clone), RAMPS 1.2, teacup firmware and, at the moment ReplicatorG software as this is the only one I seem to be able to get working reliably on my Macbook Pro OSX 10.6. Teacup is built with standard RAMPS 1.2 config file.

The X, Y, and Z axes are moving OK from the ReplicatorG control panel (jogging) but I can't get the extruder to move. It seems as though there is no power to the extruder motor as it will turn easily by hand when main power is on while all other motors are locked. I have swapped the Pololu drivers about to confirm that there is no problem there and have swapped the X-axis and extruder motors over to confirm its not a motor problem. I don't yet have the limit switches or thermocouple and heater wired in - one step at a time...

I have built a couple of cnc machines running on EMC before with home built electronics but this is my first foray into Arduinos and so I don't really know whether I have an electronic problem or just a lack of knowledge on driving the software...

Is it just me or do I have a problem - if so, where?

Thanks, Ian

You should try printrun, i've been using it with my Ramps 1.2 and it does what I need, SD printing works great too
From github: "This alternative approach is confirmed to work on Mac OS X 10.6.8."

[github.com]

When did you download the teacup firmware? Recently, I found that the statement to reverse the logic for the enable signal for the extruder stepper is missing in the configuration file: [forums.reprap.org]. Traumflug corrected the latest version.

You might also want to look at Marlin firmware. It does at much better job with acceleration .

Thanks - I looked at printrun ( pronterface ) but couldn't make much sense of it. The Teacup firmware I have is "triffid-Teacup_Firmware-61b81b8-1". I'll have a look at what you recommend. I'm a bit hampered at the moment with only having my Macbook available - my daughter has temporarily hijacked the linux / windows laptop I will probably use to run the machine long term - the macbook doesn't have half the enthusiasm about running non-Apple programs as does the linux machine......