Let's start with the soldering the LED matrices to the Backpack. After all 32 pins have been soldered, carefully trim the pins with a flush cutter.
Use a pair of pliers to straighten the legs of the two pushbuttons and then insert them into the cavities on the left side of the enclosure.
On the inside, you should be able to see all four pins of the pushbuttons. Bend the inner two and join them together with some solder.
Now prepare two resistors and two short piece of wires - approximately 4cm and 5cm respectively - and solder each wire to a resistor.
Then solder each of them to the outer two pins of the pushbuttons. The 4cm wire on the left, 5cm on the right.
To prepare the joystick for soldering/mounting, straighten its legs, bend them 90 degrees outward, and then cut them to about half the length.
Put a little bit of solder on all six pins.
Prepare 5 pairs of resistors and short wires (about 8cm each). We'll cut them to the exact lengths needed later.
Solder the five resistors to the five pins on the joystick. Make sure the solder makes firm connections between the resistors and the joystick.
Push the joystick into the square opening. It should be a tight fit. If not, put a little bit of super glue along the seam to fix the joytick in place.
Now push the LED matrix backpack into the largest opening, and use four M2 screws to secure it in place. Make sure that the I2C pins (VCC, GND, SCL, SDA) are near the top of the device.
Solder the two white wires from the pushbutton resistors to the 1st and 2nd pins on the left side of the top LED matrix.
Then use a yellow wire to connect the joystick to the solder joint between the two pushbuttons, and another to connect the solder joint to the 3rd pin on the left side of the top LED matrix.
Solder a white wire to each of the resistors on the left side of the joystick, and make the connections shown in the picture above. If the picture looks confusing, please refer to the circuit diagram on the previous page.
Then we can solder the last set of wires to connect the two resistors on the right side of the joystick to the backpack. Again, please refer to the circuit diagram on the previous page if the picture looks confusing.
Now we have the top half of the Tiny Tetris with all components assembled and wires soldered.