Duet 3 mini Expansion
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Is it possible to expand the IO inputs on the Duet 3 mini?
I have all but one occupied and would like to control two more rc servos.
Otherwise I would have to home the Y axis sensorless to get an input free -
@Proschi78 Perhaps with a toolboard?
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@Proschi78 if you are not using a temperature daughter board, you can use the two CS pins on the connector as additional inputs or non-PWM outputs. Be careful because there is no protection on those pins.
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@dc42 thanks I will try it on the CS pins
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@Proschi78
ok i have now connected the servo to spi2.cs1.;Servo configuration M950 S1 C"spi2.cs1" ; assign GPIO port 1 to out9 (Servo header), servo mode
what command do i use to move it now?
M280 P# S80 ?
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@Proschi78 you asked about expanding the IO inputs. To control a servo, you need an output, and it must be PWM-capable. The SPI CS pins can be used as low-current outputs, but they are not PWM-capable.
Do you have any of the four low-current outputs free? They can be used to drive servos, in conjunction with an external pullup resistor. Connect the OUTn_NEG pin of the output to the servo control wire, and connect a resistor in the range 2K to 10K between that connection and +5V. You will need to get +5V and GND for the servo from a different connector. Be careful not to connect the servo to the VFAN [in of the OUT connector by mistake.
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@dc42 ok then i could put a filament sensor or limit switch on a cs in right?
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@Proschi78 said in Duet 3 mini Expansion:
@dc42 ok then i could put a filament sensor or limit switch on a cs in right?
Yes.
It's OK to use the input and output pin of an IO connector for different purposes, for example to drive a hobby servo and read and endstop.
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@dc42 OK thank you
then I will solve it like this