Adding a battery

Since the Cart Reader does not need a PC to operate you can make it truly portable by adding a battery.

Warning: Only use a high-quality battery with integrated protection circuit you bought from a reliable vendor. Check for short-circuits in your soldering work before inserting the battery. Never insert the battery into the holder the wrong way.

1) First you need to buy this battery module and a matching 18650 battery.

2) Next connect the battery module to both the Arduino Mega and the Cart Reader shield.

Connect blue to blue, red to red, orange to orange and brown to brown.

3a) If you want just the simple backplate print out these new parts (1) (2).

3b) If you want the full case print out these new parts (1) (2) (3) (4)x2

4) In both cases you will also need these parts if you did not already print them earlier (1)print with clear PLA (2) (3)

5) As soon as you plug in a microUSB cable into the Arduino's USB port the 18650 battery will be charged at 500mA. The battery module will automatically convert the 3.7V of the battery to 5V for use with the Cart Reader. The switch and the two USB ports on the battery module do not serve any purpose anymore. In this configuration there always has to be a battery inserted into the battery module or else the Arduino will not turn on. Sometimes if the Arduino does not turn on you have to plug a USB cable into the battery module and then turn the Cart Reader on.