An H-bridge is high-low in one direction and low-high in the other. high-high and low-low both mean stop. beyond that I recommend moving to Arduino as this is about an arduino specific piece of hardware- the motor shield
An H-bridge is high-low in one direction and low-high in the other. high-high and low-low both mean stop. beyond that I recommend moving to Arduino as this is about an arduino specific piece of hardware- the motor shield