NOTE: The watch battery shown here is the CR2032 Lithium Battery 3V Button Cell. The chip shown, ATTINY85V, has a minimum working voltage of 1.8 Volts while the ATTINY85 has a minimum voltage of 2.7. It is advised to use a chargeable button cell with both versions of the ATTINY85/V chip.
1. Place the board as shown above.
2. Turn the board from left to right.
3. Each copper line carries electricity from left to right or from right to left. Each line is called a bus or a rail and are separated from each other by a thin line of plastic.
4. Turn the board from left to right. Count down 3 holes and draw a straight line, then count down 9 holes and draw another straight line from left to right. Label the top + and bottom -.
5. Insert the battery socket as shown. Make sure + is on top and solder. Correct orientation is crucial.
6. Insert the battery into the socket after verifying that it is good with the multimeter. Attach the red probe hook to the + rail and the black probe hook to the - rail. Check that the reading is about 3.1 V.
7. Insert the chip socket as shown and solder.
8. After soldering, cut a line through the rails so that the opposing pins do not communicate.
9. Insert connecting cables to connect the power. Bottom-left to negative, upper-right to positive. Draw an arrow now in the upper left corner. This power configuration is for the ATTiny85 IC.
Solder power cables in. Keep the ends of the cables on the copper rail.
10. Test the 2 outlets on the socket by inserting a wire into the socket and connecting the voltmeter. Voltmeter should read about 3.1 V.
11. Label the pins as shown. Insert the positive lead of the first set of LEDs into Pin #1 anywhere on the rail, the second set of LEDs into Pin#0. (Pin 0 is the bottom right-hand pin) Solder, bridging the cable to the pin weld.
12. Connect the negative cables of the LEDs on the negative bus. Anywhere on the line. Solder them. Turn the board over and apply negative power from a 5V source to the negative rail and positive power to the back of the Pin # 0. The LED should light. Apply this test to pin # 1. If the LEDs do not light, you have made a mistake in your welding. Resolve the problem.
13. Obtain the switch assembly. Check the continuity with your multimeter to make sure it is good. Connect as shown. When you press the button, you should see some voltage record. Be sure to switch the selector to the continuity option on your multimeter.
14. Insert the 10K resistance (either leg) into the negative rail, the other leg over a few holes. Solder the leg in the negative rail and the other in its own rail. There should be nothing else on the second leg rail.
15. Connect one cable of the switch to the positive + rail and the other cable to the 2nd leg of the resistor.
16. Connect the bottom leg of the resistor to the chip Pin #2 as shown in orange.
17. Insert the chip. Put the little dot that is on the chip in the upper left-hand corner of the socket. Orientation is critical.
18. Insert the battery and press the button.
19. Whew, electronics DONE! Well, press the switch a few times to turn off and on.