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Confirmed 2 Wire - No level-shifter - Open Drain Works > Connection for smoothieboard

Disclaimer by the author +Don Kleinschnitz and tester PLEASE READ
As promised, I completed testing the two wire, no level-shifter, Open Drain approach to PWM control. Tests were performed under various power and controller transitions. I found no cases where the laser fired erroneously.

Keep this in mind:
1. These testing results should apply to all machines with EXACTLY the same configuration as mine. Your results may vary. YOU are responsible to test your own machine. Let me know if you get different results.
2. Good control design does not eliminate the need for interlocks. There are failure and error modes that can cause a laser to fire erroneously. You must still have interlocks installed and operational for a machine to be capable of "SAFE" operation.

By reading this you acknowledge that you use this information at your own risk.

Details in his blog >
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