Hello again.

Having 8 wires out of your motor means that the four coils are wired independently. The trick now is to identify every pair and their polarities.

While the appended diagram might help there is a procedure you can use to identify them.

You can use an ohmmeter to identify the coils. Simply choose one wire and touch the others one by one. The one with a reading is the right one. I´m sure you know that.

To identify the complementary coils an old trick prove useful. Your will need an old analog voltmeter or ammeter. While one with a centered zero is better any will do. Digital meters can be used but due to their sampling period the result might not be clear.

Once you have the coil wires identified select two coils connecting the voltmeter or ammeter to one of them and give a small touch with a voltage source to the other. You can use the ohmmeter for this.

Now watch for the deflection of the meter. Keeping the powered coil repeat the procedure on the other two coils. The largest deflection will identify the complementary coil to the one being excited.

Remember that the deflection is momentaneous. That´s why a digital meter is not recommended for this procedure.

The direction of the deflection will tell you the polarity of the coil. A negative deflection will tell you that the positive and negative sides of the coil match those of the meter.

Finally repeat the procedure in the two other coils to identify their polarities.

After that connect every pair joining together the positive terminal of one of the coils to the negative terminal of the other. The extremes are the wires to be connected to the driver.

In any case I suggest you try the drive at low voltages first.

To make an easy jig to try motors and amplifiers I use an NE555 based oscillator and a switch for the direction.

In my systems I use the small card shown. It has no more than a ULN2803 and 5 3,900 ohm 1/2 Watt resistors. This card connects the LPT port of the control computer to the drivers. The 5V required are taken from the PC power supply.

I don´t know if this card can serve as a breakout board for other systems than mine.

I hope this helps.

Regards.