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CNC controller - port pin pullups/downs?

2003-10-12 by ghidera2000

I'm just finishing up the design for an A3977SED based controller 
board but I'm a bit confused about the parallel port connections.

Can the parallel port drive logic high and low or does it just go 
active low (sinking) and high-Z? i.e. Do I need pullups to generate 
logic high, or can the parallel port handle this just fine?

I plan on pulling Enable high on the board and setting it to active 
low in the software. That way if the cable pops out I know the 
drives will stop.

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