Cool work, thanks! - I'll have a look over it and give it a shot later this weekend!

thanks!
sn

I know Seth hasn't replied here yet, but I'll weigh in. I forgot to update this thread to say that I eventually did merge the changes into polargraph_server_a1, albeit in a slightly different form.

You need to change the first set of #defines in polargraph_server_a1.ino to make sure that UNL2003_DRIVER is the only line that is not commented out:

//#define ADAFRUIT_MOTORSHIELD_V1
//#define ADAFRUIT_MOTORSHIELD_V2

// Using discrete stepper drivers? (eg EasyDriver, stepstick, Pololu gear),
// choose SERIAL_STEPPER_DRIVERS and define your pins at the bottom of 'configuration.ino'.
//#define SERIAL_STEPPER_DRIVERS 

// Using a signal amplifier like a UNL2003? 
#define UNL2003_DRIVER

Then you need to comment out all of the #include lines at the top of in configuration.ino that would usually load the adafruit libraries.

The bit you're interested in is the motor declarations:

AccelStepper motorA(8, 6,8,7,9);
AccelStepper motorB(8, 2,4,3,5);

configuration.ino

Those numbers (6,8,7,9 and 2,4,3,5) are the arduino pins that Seth used to wire up the UNL2003s.

That's a good question. http://www.airspayce.com/mikem/arduino/AccelStepper/classAccelStepper.html#a73bdecf1273d98d8c5fbcb764cabeea5 has the answer.

But I think this means: "(8) means a 4 wire half stepper (4 pins required)". That page linked to above has a better description of the different AccelStepper settings.

It's better to use AccelStepper::HALF4WIRE instead of 8, because it actually means something. AccelStepper::FULL4WIRE might be a good one to use too.

sn

Cool, you're into the realms of serial port debugging here, so basically lots of plugging, unplugging, resetting, waiting, combinations thereof.

Essentially, if you've managed to upload the code, then you've got it working. At least, you know it can work. Close Arduino, open the Polargraph Controller and choose the serial port from the subwindow that opens when you go to setup -> serial port.

sn

Aha, good spot. Off the top of my head, it's only the speed settings (and stepsPerRev) that are in steps, everything else should be mm.

Set the mmPerRev, stepsPerRev and stepMultiplier first, then start setting the size of the machine.

Hello!

I am currently trying to get this set up myself (ULN2003A) and I'm fairly certain that everything is wired up correctly. I have uploaded a sketch to the Arduino and from there I can attempt to move the pen to a point in Polargraphcontroller but as i click to confirm the point it starts up and will only run clockwise on both motors despite what area of the controller I click on.

I may be totally off base here but what I gathered was that I was as well supposed to switch pins 7,8 and 4,3?

Hopefully y'all have some idea what may be happening but if not, I hope ya'll having a good night.

The pins that are specified in the accelstepper declaration are important, but only insomuch as the map directly to the motor wires. The original code was switched and worked fine for the original writer, so lets agree that there are many ways of wiring these modules up, many kinds of motors, and in fact many different ULN2003 driver modules, some of which might well map input pins to motor wires in a weird way.

At the first problem, you should load up one of the accelstepper example sketches, and make sure you can get things running WITHOUT all the extra baggage of the polargraph stuff around it, that also all needs to be got right to work.

The examples are listed at http://www.airspayce.com/mikem/arduino/AccelStepper/examples.html, but you can load them in Arduino through file->examples->accelstepper.

Not a straightforward way of doing it using the standard polargraph firmware, but you can easily knock up a little arduino sketch that will run for a couple of thousand steps, reporting it's position, and you just make a note at which step number the motor has made one full turn.

http://forum.arduino.cc/index.php?topic=91243.0

sn

Hey! Sorry for jumping into an old post, but I'm attemping to use this very bit of code. I've got some 28YBJ-48 steppers with the ULN2003 drivers hooked up to an arduino. Everything compiles correctly but I'm not getting any motion on the steppers. However, I also noticed this line:

//for a 28YBJ-48 Stepper, change these parameters above
//Step angle (8-step) 5.625deg, 64 steps per rev
//Step angle (4-step) 11.25deg, 32 steps per rev
//gear reduction ratio 1/63.68395

But I'm not understanding it, could someone explain what is meant here?

Hi. Sorry for touching this ancient thread, but there is an issue with this code:

// MotorA
//ULN2003  Arduino  AcceStepper Init
//IN1      2        2
//IN2      3        4
//IN3      4        3
//IN4      5        5
// MotorB
//ULN2003  Arduino  AcceStepper Init
//IN1      6        6
//IN2      7        8
//IN3      8        7
//IN4      9        9

.......

AccelStepper motorA(8, 6,8,7,9);
AccelStepper motorB(8, 2,4,3,5);

It looks like motorA and motorB are swapped in wiring diagram (actual code appears to be OK).

MotorB is moving in the wrong direction, and changing first argument in motorB.setPinsInverted(true doesn't help. Any ideas?