OK.
D4 - polarity switch
D5 - rise / fall
D6 - controls AC - DC output
Can you explain more to me about the three switches. I understand the polarity switch which will control which comes first +12 or -12.
Is D6 to use the current unipolar output or the new bipolar mode? Previously you said that the bipolar output would replace the current mode. If we are keeping it, what pin is the output on?
EDIT: Is pin6 the switch which currently sets the charge pulses active?
Do you still want to keep the rise/fall return timing start option? In the bipolar mode, Do you know which of the two pulses(+12v, -12v), and which edge do you want to start timing from?