Parts

• 1 custom motherboad
• 1 Arduino Nano
• 1 2.5mm power jack
• 1 2pin 2.54mm SIL Header
• 1 2.54 link
• 1 4pin 2.54mm SIL socket
• 1 4pin 2.54mm SIL Header
• 1 SSD1306 OLED display breakout board

Step 1: Attach nano

• Take the custom motherboad and insert the Arduino Nano as shown.
• Solder the pins of the nano to the motherboard.
• Trim the excess of the pins.

Step 2: Solder jack and header

Solder the 2.5mm power jack and 2pin 2.54mm SIL Header to the motherboard.

Step 3: Attach link

Connect the 2.54 link to the header.

Step 4: Solder 4-pin socket

Solder the 4pin 2.54mm SIL socket at the far end of the motherboard

Step 5: Solder breakout board

• Insert the [MAX30100 or MAX30101 Breakout Board] into the mother board on the opposite side to the Nano
• Solder the breakout board connections

Step 6: Connect the display

Using the 4pin 2.54mm SIL Header connect the SSD1306 OLED display breakout board to the 4-pin socket.

Next steps

The electronics are now ready for mechanical assembly of the finger clip or firmware upload. Make sure that firmware is loaded onto the nano before assembly of the finger clip.