Extruder firmware driving DC motor

Hello,
I'm building a Mendel for school (thesis) and I'm going to use a mk4 plastruder from makerbot.
Now my problem is that its a DC motor while the reprap firmware expects a stepper motor. Could anyone help me with modifying the firmware so it'll work?
I already looked at the configuration.h file but there is no option for it.

Thanks,
DeLaVega

Which firmware are you using? Where did you download it from?

Which version of the electronics are you using?

I'm using gen3 electronics from makerbot and got the firmware from the RepRap Subversion repository. I'm using the latest version from that page.

The idea behind 5D is to specify the length that the extruder should extrude. This makes sense for a stepper, which is controlled by steps, but not for a DC motor, which is controlled by speed. I can't find any way to make the DC motor work with that firmware (without major modifications).

The Generation 3 firmware might work better for you. [reprap.svn.sourceforge.net]

In ArduinoSlaveExtruder/configuration.h there is a MOTOR_STYLE option, which should get you what you need.

More info: [www.reprap.org]

Edited 1 time(s). Last edit at 12/15/2009 03:26PM by mccoyn.

ok, I uploaded the gen3 firmware but now i don't get any response from the motherboard. I tried reprap-mendel-20091106 and reprap-host-windows-20090613.
Is this normal or did I do something wrong?

Thanks,
DeLaVega

this is both normal, and wrong. it's quite normal for complicated firmware to not behave as you expected because of bad wiring, or bad code ( eg, are you end-stops correctly wired, and is your firmtware configured to expect the same logic level as your endstops provide ), I suggest you try small chunks of "test code" to make sure that each pin is connected and behaving as you desire.

As for your DC motor controller issue, I guess that the firmware you want to use is one of the makerbot derivative/s as these have DC motor controls and work with gen3 electronics ( ie a dual-arduino setup). you may end up hacking your own firmware like i did.

Buzz.

Everything worked fine with the 5D firmware, but now I don't even get a response in the debugging window.