In the hardware  I have connected a mpg to port 2.The Mpg has   Channel A, pin 2 Channel B, pin 3 Channel A- pin 20 Channel B- to pin 21 ..In Mach 3 under ports and pins I have Mpg 1 enabled I have A port =2 .. A pin =2,,,  B port 2 ,,,B pin =3....How do I tell it I have a ..A-Channel connected to port 2 pin 20 and a B- Channel connected to port 2 pin 21 ? Thank you. You guys are great.