Figure 5. One cycle of dynamic communication between MB and Mobile phone. The messages shown in the diagram will cause stepper motor 0 to do 10 steps clockwise and stepper motor 1 to do 10 steps anti-clockwise

From

BlueSteps: A Bluetooth Based Stepper Motor Control System

Ifrah Jaffri, Zeeshan Nafees, Shoaib Zaidi, Oliver Faust

Journal of Embedded Systems. 2015, 3(1), 21-27 doi:10.12691/jes-3-1-4