ah they call it something different, good old maplins.
im assuming its exactly the same and wired the same? (electronics is not my fing)
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A slotted disc attached to the spindle, an Optek OPB 916B optical switch and a 220 Ohm resistor are all thats required. Take 5v from the BOB to the white wire on the opto, take the same 5v source to one end of the resistor and connect the other end to the red wire on the opto. Connect the Green and black wires of opto together and connect to 0v (Gnd) terminal on Bob. Take blue wire from opto and put to an input on the BOB. In Ports and Pins, Inputs set p the Index to the port and pin you have it connected to.
BTW Mach has to be licensed for threading just in case you are in demo and wonder why it doesnt work.
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