I have an issue about the breakout board , i can't understand why i get ( -5V) instead of ( +5V) when i measure the voltage between the "Dir" pin and " com" pin

It sounds like the meter red and black wires are being switched around. The breakout board should not be giving you a -5 volts. The voltages should be in the range of 0 and 5 volts. The voltages will change when you move the axis in one direction or the other.