I know. I'm clueless. Today the clues narrowed, but I don't know again for sure: The same example from yesterday, the same motor and no shield, just the ULN2003A. Tested my serial comm with processing all day long because I want to move to a different stage. Suddenly I noticed some hours ago, that this is also going FORWARD all the time. Even though it worked since Yesterday.
I almost collapsed! thought I had an alternative, and now this doesn't work either. This leaves me with 3 theories:
1. Can it be something with Voltage? I'm using a switching power supply with this specs: PRI: 100v-240v-60/50Hz 0.16A it can be set from 3v to 12v
2. Can the motors be damaged? I have just 2, so I just wonder if this is possible.
3. Or can the Arduino be doing something weird? I guess not, the other part of the project is going fine, and all seems to go normally. I have a very commented communication warning with processing (rxtx mismatch), but it doesn't affect data transfer...
This is my first project with motors, so I could have done something terribly wrong (Like powering the whole thing with the bare cables or whatever). The example you ask for is also not working: from all the commands, the motor will just move twice FORWARD, when it comes to DOUBLE steps. Tried changing speed and steps, but the motors will not respond.