Optical end stops on a duet, can I use them?

Is it possible to use optical end stops on a Duet control board and if so what
will I need to change in config.g and how should I connect them up?

I have some Honeywell H0A1887-12 which I know I will have to add a resistor for the LED current limit
but will I need to put a pull up/down resistor on the output, and which pins do I use on the duet

Don

Starting from the pin next to the corresponding motor pins, the endstop pins on the Duet are Signal, +3.3V, and Ground in that order. So you need to connect the light emitting side of the sensor to +3.3 and ground through a series resistor of about 82 ohms to get the recommended 20mA forward current. It will quite probably work without a pullup resistor on the output, but if you find it responds too slowly, try a 10K pullup resistor between the output and +3.3V. I don't recommend you use much lower than that, because the output of that sensor is quite weak and it already has to drive the endstop LED. You won't need to change config.g.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks Dave

I will give it a go

Don