Category Archives: Arduino

Arduino Projects and tutorials.

Use the FTDI Basic Breakout Board to program an Atmega328P-PU With Optiboot.

This is if you want to program your breadboard arduino and have an atmega328P-PU with the Optiboot bootloader already on the chip. The biggest issue I have found with breadboarding any chip is that they don’t always want to fully seat into the breadboard. In my experience, I find that pressing firmly down on the chip while uploading saves a ton of trouble!

The LED attached to pin 19 (D13) of the chip is there just as an example. I usually upload the example Blink sketch first to verify that I am able to upload a sketch since it gives me visual confirmation.


If you are using an oscillator.

Note: the caps with the oscillator are pF, NOT uF. Sorry.



If you want to use the FTDI Basic Breakout Board for timing.



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Arduino 3.7 Volt LiPo Battery Meter

There is probably room for improvement here but this is what I have come up with for a 3.7 Volt LiPo battery meter. In the picture below I am charging my battery from a 5 volt source. All the charge controlling circuitry is built into the battery. I just wanted a way to monitor the charging progress, although, this could certainly be added to any project that uses a 3.7 volt LiPo battery for its power supply.
Hope this helps.

//3.7V LiPo Battery Meter
//3.7V LiPo Battery Meter
//Use two 1.2 K Ohm resisters as a voltage divider from the positive
//and negative terminal of the battery to read reference voltage from.
//we wouldnt want to send to much voltage to our Arduino.
//Make sure to tie the ground back to the Arduino. Otherwise, expect some odd readings.

int sensorPin = 0; //set up the sensor pin for reading the voltage
int sensorValue = 0; //variable to store the value coming from the sensor

void setup()
//This is the default value, but we can set it anyways
analogReference(DEFAULT); //5V Reference on UNO
Serial.begin(9600); //initialize serial communication

void loop()
sensorValue = analogRead(sensorPin); //set sensorValue as an analog read of the A0 pin
//print the value of the sensor multiplied by 0.00326 to get true voltage reading.
//this is a value of 0 – 1023 coming from the sensor pin and has to be converted.
Serial.println(“Battery Voltage Is”);
Serial.println(sensorValue * 0.00951);

delay(1000); //give a delay between readings.