I have my own Arduino code and processing is generating the xy mouse movement and sending it to the Arduino. But, my problem is understanding how to make the packets small as you have described. Since the Processing is sending the xy data, I assume that I can "package" the data in small pairs but I am not sure hoe. Thanks for the insight!
Thanks Grumpy_Mike and I am not sure if you are suggesting that I use the G code language or that I should be looking at how I am using the code to send the data and incorporate some sort of packet command. Any clarification would help.
I constructed an xy plotter and use Processing to send mouse data serially to the Arduino, then to Easydrivers, and then to the steppers. It works fine except that being serial, I can send an "x" or a "y", but not both simultaneously. The result is that only one stepper can be moving at a time. So, I can't make a diagonal line easily or make any move that requires both steppers to move at the same time as in a circle for example. I am thinking about using a shift register to store the x and y data and feed it as parallel data allowing the plotter to move both steppers at the same time. The speed of transfer is not important at all. The thought is that a shift register conversion after the Arduino could be stored, if needed, and then fed to the Easydriver chips. I would appreciate any thoughts or suggestions about the possibility of this approach.
The sleep, ms1,ms2, and enable pins on the Easydriver should be tied high or low with 10K resistors. For the code from PaulS, you can use full step only so tie ms1 and ms2 low. (10K resistor from pin to ground rail). Tie enable pin low as well, and sleep pin high. (Pin to +5). The + voltage should come fro the V+ on the Easydriver and not the stepper V+ which must be isolated! As bigE, I have constructed an XY plotter and the code from PaulS works really well but I have one problem. The movement on the plotter is very small and I have not figured out how to make the stepper movement fit my plotter, 13X13 inches. I have difficulty with code but not electronics. Peace.