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General Mach Discussion / Re: Motor "Sometimes" goes in Wrong Direction while Tuning
« on: March 18, 2009, 04:05:24 PM »
Yes thats correct, its commonly called Gnd but really its 0V, doesnt matter whether its the BOB or the Drive as they are one in the same with a non powered BOB, so whichever gives you easiest access.
The 5v it is getting is from the parallel port which ultimitely is coming from your computers PSU and yes it will be adequate, however modern design of parallel ports often has them powered by 3.3v rather than 5v which causes problems with the drives not picking signals up properly on occasions. Using a powered BOB will eleviate this problem as the BOB will be happy with the 3.3v signals from the port but it will put out 5V so that the drives are happy. As was mentioned optically isolated BOBs are not always a good thing when it comes to drives that have optos already in them, so best to make sure any powered BOB you may get doesnt have optically isolated outputs for Step/Dir pins.
Hood
The 5v it is getting is from the parallel port which ultimitely is coming from your computers PSU and yes it will be adequate, however modern design of parallel ports often has them powered by 3.3v rather than 5v which causes problems with the drives not picking signals up properly on occasions. Using a powered BOB will eleviate this problem as the BOB will be happy with the 3.3v signals from the port but it will put out 5V so that the drives are happy. As was mentioned optically isolated BOBs are not always a good thing when it comes to drives that have optos already in them, so best to make sure any powered BOB you may get doesnt have optically isolated outputs for Step/Dir pins.
Hood