assembly.md
April 2, 2020 ยท View on GitHub
LetheKit Assembly Instructions
The following steps fully detail how to assemble the LetheKit from its parts.
Assemble the Switch Harness
Parts: Jumper Wires, Rocker Switch
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Separate (pull apart) a black/white pair from the Jumper Wires. Cut this pair in the middle and strip 1cm of the ends on one of the halves.
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Separate a brown wire from the jumper wires. Cut this wire in the middle and strip 1cm of the ends on both halves.
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Twist the stripped black lead together with the two stripped brown leads and solder to post "1b" on the Rocker Switch (under the "1" part of the switch).
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Solder the white lead to the center post of the rocker switch.

Assemble the Waveshare Display Harness
Parts: Waveshare 200x200 Display Module, (optional) Cable Ties
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The Display Module comes with a cable that has a display connector on one end and individual jumper connectors on the other. Attach the display connector end to the display.
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It's helpful to add a small Cable Tie (or similar) to the middle of the cable cluster to help keep the wires together.
Connect the SAMD51 Headers
Parts: Break Away Male Headers, SAMD51
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Break the Break Away Male Headers into a 12-pin piece and a 16-pin piece.
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Solder the headers onto the top of the SAMD51 with the pins facing away from the board.

Add a Jumper to SAMD51
An extra ground pin is required on the SAMD51 header. Luckily, there is an unused (not-connected) pin that can be commandeered.
Parts: connected SAMD51 with Headers
- Solder a piece of wire bridging the GND and NC pins on the bottom of the SAMD51.

Attach Display Harness to SAMD51
Parts: assembled Waveshare Display Harness, connected SAMD51 with Headers
- Attach the Waveshare Display Harness to the SAMD51 as shown in the picture.

Assemble LED Wires
Parts: Jumper Wires, connected SAMD51 with Headers
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Separate a blue and green pair from the Jumper Wires. Split the pair most of the way to one side.
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Attach the non-split side of the pair to the SAMD51 as shown.

Attach Keypad to Case
Parts: Membrane Switch Keypad, 3D Printed Case
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Insert the Membrane Switch Keypad connector through the slot at the bottom of the Case front.
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Peel the adhesive cover off the back of the Keypad and press it into place on the Case as shown.

Attach Display to Case
Parts: Waveshare 200x200 Display Module, 3D Printed Case, 3/16" Phillips Rounded Head Screws
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Gently attach the Display Module to the Case with Phillips Rounded Head Screws. DO NOT OVERTIGHTEN SCREWS. There are two sets of display holes to support an alternate display; use the set which aligns the display in its cutout when viewed from the other side of the case.
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It's helpful to dress the display wires towards the bottom of the case as they leave the display connector so that they will clear the LED when it is inserted through the hole.

Attach LEDs to Case
Parts: Blue LED, Green LED, LED Holders, 3D Printed Case
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Trim the LED leds a little. Trim the longer lead to 18mm length from the base of the LED and the shorter lead to 16mm. The lead length is used to identify polarity so it's critical to keep the longer lead longer than the shorter lead.
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Insert the Blue LED into an LED holder and snap it into place in the hole in the side of the Case, above where the power switch will go. It's helpful if the LED's leads are horizontally oriented.
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Insert the Green LED into an LED holder and snap in into place in the hole in the front of the case. Bend the leads in a 90-degree angle, down towards the bottom of the case. Again, it's helpful if the leads are oriented horizontally.

Attach the Switch to Case
Parts: Rocker Switch, Switch Harness, 3D Printed Case, assembled SAMD51 with Headers
- Snap the Rocker Switch into place in the Case. Orient the Rocker Switch so the "1" side is towards the top of the case.

- Connect the white and black Switch Harness leads to the SAMD51 as shown.

Insert Battery
Parts: Lithium Ion Battery, 3D Printed Case
- Place the Lithium Ion Battery into the guides in the Case as shown.

Install Battery Shield
The shield prevents the SAMD51 module from damaging the surface of the battery.
Parts: 3D Printed Battery Shield
- Place the Battery Shield on top of the battery in the guides as shown.

Connect the Keypad Connector
Parts: Membrane Switch Keypad, assembled SAMD51 with Headers
- Connect the the Membrane Switch Keypad connector to the SAMD51 as shown. Note that the connector fits "one pin in" from the end of the header.

Attach SAMD51 to Case
Parts: assembled SAMD51 with Headers, 3D Printed Case, 3/16" Phillips Rounded Head Screws
- Fit the SAMD51 into is mounting location on the Case. Attach with **Phillips Rounded Head Screws*8. DO NOT OVERTIGHTEN THE SCREWS.

Connect LEDS
Parts: Blue LED, Green LED, LED Wires, Switch Harness
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Connect the green wire from the LED Wires to the longer lead of the Green LED.
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Connect the blue wire from the LED Wires to the longer lead of the Blue LED.
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Connect one of the brown wires from the Switch Harness to the shorter lead of the Green LED.
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Connect the other brown wires from the Switch Harness to the shorter lead of the Blue LED.

Connect Battery
Parts: Lithium Ion Battery, assembled SAMD51 with Headers
- Carefully connect the Lithium Ion Battery to the SAMD51. Support the SAMD51 as you insert the connector to avoid stressing the attachment screws.
IMPORTANT - Always first disconnect the battery when working on the inside of the terminal to avoid damaging the cicuits.
That's It!

Attach the Cover
Parts: 3D Printed Cover, Push-in Bumpers, 1/2" Flat Head Screws
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Press the Bumpers into the Cover.
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Attach the Cover to the Case with the 1/2" Flat Head Screws.