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grblHAL core code and master Wiki
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Are the all inputs like e-stp, homming, probe, pins pullup ? #534

Open RDS356 opened 2 weeks ago

RDS356 commented 2 weeks ago

Not a issue, just a doubt.

I'm building my board, is necessary pullups resistors on the inputs ?

Thanks. Regards, Reinaldo de Souza

terjeio commented 2 weeks ago

I'm building my board, is necessary pullups resistors on the inputs ?

If you want an EMI resistant board then not only pullup resistors (and filter capacitors) are needed, but optocouplers are as well. You want the energy contained in any noise to dissipate without doing any harm and the best way to achieve that is to use NC (normally closed) switches and low impedance inputs. IMO optocouplers are a must in any serious board design and will provide low impedance inputs, some low pass filtering and electrical isolation - even with separate ground if you chose so.