Arduino question: I want 2 stepper motors to run at the same time.

Hi, I have 2 arduinos, 2 motor shields, and 2 stepper motors. I want the 2 motors to run simultaneously, when I connect the 2 steppers to one arduino, the motors do not run at the same time. For example, in a for loop like this, motor 1 will run, stop, then moto 2 will run, stop.

for k=1:3;

a.stepperStep(1,'forward','double',200);

a.stepperStep(2,'forward','double',200);

end

The same issue occurs if I have 2 arduinos connected. For example, the for loop would be like this:

for k=1:3;

a.stepperStep(1,'forward','double',200);

b.stepperStep(1,'forward','double',200);

end

with "b." representing a different arduino than the "a."

Is there a way to make the 2 motors run at the same time?

Thank you.

[Walter Roberson]

duplicate is http://www.mathworks.co.uk/matlabcentral/answers/56833-how-can-i-run-2-stepper-motors-simultaneously-connected-to-an-arduino-uno-using-matlab