The New Features
I've added 3 new features which are as follows:
1. 2 new buttons to control the brightness. This is just a temporary version, I just want to check whether it is nice to have a button and to control the brightness. It turns out that yes, it is indeed needed. I still am thinking if I will make this permanent because I plan to control the brightness, contrast, set time and date, store important dates and alarms using the pc. I connected the 2 buttons using the schematic below:
2. A back-up battery with Charger and DC-DC Step Up converter. The clock will not be connected to the pc 90% of the time so a battery is needed to power it up and must be rechargeable just like cellphone. I used the AREF pin to bypass the on board regulator of the arduino because it is not efficient. The battery is rated 3.6V so it is not enough to power-up the arduino that is why I need to bost that voltage to 5V using the DC-DC Step-up converter. Below is the connection diagram I used:
3. A software feature to monitor the battery charge. Using the diagram above, I connected A1(analog pin 1) of the arduino to the positive terminal of the battery to measure current charge of the battery. I used the following codes:
val3 = val3 + analogRead(1);analogRead(1) will return values between 0 to 1023 which is summed up to val3 40 times and the average is taken and converted to voltage reading.
charglim++;
if(charglim>40)
{
val3 = val3/charglim;
val1 = val3/204.6; //0-5V
charglim = 0;
val3 = 0;
}
Here's the actual pictures of the components I used:
Some of the components I used can be bought from my sulit shop http://n92seller.sulit.com.ph
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