The NeoMatrix Mk I circuit is diagrammed above. You can refer to this while connecting the components during assembly.
Keypad
Begin assembly by affixing components to the inside of the front panel, starting with the keypad.
The keypad fits in place from the inside and you can then secure it with four of the 9.5mm long M2.5 nylon screws and nuts. |
Display Modules
The NeoSegment modules will also be assembled from the inside of the front panel, however, they require a bit of preparation first.
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Metro Mounting
We'll use nylon hex standoffs to mount the Adafruit Metro board to the inside of the front panel.
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Potentiometer Mounting
The two potentiometers will be mounted from the inside of the front panel and screwed into place with their included hex nuts.
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PushbuttonUnscrew the retention collar, then fit the button into it's hole in the left side panel, then screw the collar back on. |
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USB JackAlign the USB panel mount jack with the holes from the inside of the right side panel. Then, screw in the two provided screws. |
Wiring Everything Together
Now that everything is assembled, we need to wire all of the parts together. We'll start with the keypad.
The keypad matrix uses eight wires to send data to the Metro, which we'll set up in software for pins 2-9. We'll create a custom cable to make this set of connections.
Low Profile Interconnects
Connecting the electronics is fairly straightforward, however, in order to keep a low profile in a small enclosure, we will need to make 90 degree angle connector cables.
Voila, instant custom interconnect! |
The other end of the wires can be pressed directly onto the phone keypad pins as shown, with a piece of heat shrink tubing over each one to prevent any shorts.
Connect the cable to the Metro as shown.
NeoSegment Wiring
Just like any NeoPixel-based project, we'll need to connect power, ground, and data lines from the Metro to the display.
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Slide and heat some heat shrink tubing over the the other ends of these three wires. Then connect them to the NeoSegment's interconnect as shown here. Be sure to follow the image closely for wiring order.
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Follow the wiring diagram above and the images here for color coding and connection of the wires for the two potentiometers. In order to efficiently utilize the available pins on the Metro, we'll share the one pin each for the voltage and ground on the two pots. You can follow these images for one way to do so. |
Now, plug the ground wires into GND on the Metro, the power wires into 3.3V, and then the two center wiper wires into their respective pins, A2 and A3.
Pushbutton Wiring
The pushbutton has four contacts -- two for the switch and two for the LED. Connect the switch contacts to GND and pin 11, and the LED contacts to GND and pin 13, as shown in the wiring diagram.
The pushbutton has four contacts -- two for the switch and two for the LED. Connect the switch contacts to GND and pin 11, and the LED contacts to GND and pin 13, as shown in the wiring diagram and images here. Note: the two ground contacts on the switch have been jumpered with some wire and solder so they will share one connection on the Metro. |
Simply plug it into the USB jack on the Metro, being careful to round the wire neatly so we can close it all up next. |
Closing the Case
You can add glue to the side and bottom connections to the faceplate if you like, but just the tight fit and compression force of the four screws is enough to hold the case together nicely.
Push the four #6 screws through the front panel, then secure each with a nut |
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Fit the sides, top, and bottom to the front panel, being careful to keep the wiring neatly tucked inside. You can then press the back panel into place over the four screws -- you may need to remove one side or top panel to do this -- then screw on the nuts to secure |
Time to add the software!