Wiring the i3 mini board
DISCLAIMER: Please don't wire this board up if you're not familiar with handling electronic devices! Instead, get a pro to do it for you. Otherwise you may end up doing harm to the mainboard or even yourself! I am not responsible for any damage or loss you may cause.
This image shows you the i3 mini board layout with the connectors you need to wire it up to the SMuFF.
The Stepper motors connect to the X- Y- and Z- sockets accordingly, whereas X is the stepper motor of the Selector, Y is the stepper motor of the Revolver and Z is the stepper motor of the Feeder. Before you connect your motors, make sure you have set up the Vref correctly by using the according Potentiometers right to the stepper driver.
The endstops for the Selector, the Revolver and the Feeder go to the endstop sockets (X/Y and Z). Usually endstops need +5V / +3.3V for LEDs / pullups. You can get +5V from the ISP connector near the CPU. Don't use the sockets on the lower left end of the board to power your endstops, since these are wired to the power input of your power supply (+12V/+24V).
The Fan socket can be used to connect a PWM driven Fan to cool the drivers while operating but it's optional.
The Serial 2 socket is used to establish a serial connection with your 3D printer (usually this socket is equipped with the ESP-01 PCB). Be aware that the signal level for RX/TX is 3.3V! You might have to use a level-shifter when connecting those signals to your 3D printer. Never attach those signal to a RS-232 / V.24 connector directly. These connectors have a signal level of +-12V and will damage the i3 mini board immediately.
The communication between your 3D printer / PC and the SMuFF runs either over USB (Serial 1) or Serial 2. Baudrates can be easily configured in the configuration file. Usually no 3D printer I know of provides a USB Host connector, so the Serial 1 connection is more or less used to connect your PC for testing purposes.
If you intend utilizing a servo as the filament wiper as shown here, you have to wire the servo as follows:
- take the +5V from the ISP connector to power the servo (Red wire on the servo)
- on the plug named (Servo 1) in the picture above, connect the rightmost pin to the signal (PWM) pin (Orange wire on the servo) and the pin to the left to GND (Brown wire on the servo)
To test the connection, simply send a G12 command to the SMuFF controller.