Upon release, GB/GBC/GBA games were designed to save progress for years and years to come, but limitations unfortunately mean it won't last forever. Thankfully, the GB Operator allows you to download and store your saves digitally so they can withstand the test of time, but just how close were you to losing your childhood mementos?
The answer lies within the battery found inside the cart, and in this guide we’ll show you how to use a multimeter to find out.
GB/GBC and some early GBA games require a battery in order to store saves because the SRAM (Static Random-Access Memory) must always be powered on in order to hold the save. As soon as power is cut off, the memory is wiped and data stored on it is lost definitively. If you’re interested in learning more about how memory works on the GB/GBC/GBA, be sure to check out our article here.
To properly measure how much juice is left in the battery, you will need a Multimeter and a screwdriver (3.8mm for GB/GBC, tri-wing for GBA).
1) Use the screwdriver to open the cartridge case.
2) Switch on your multimeter and select the Voltage (V) mode.
Since GB/GBC/GBA carts use 3V coin batteries (CR2032 for GB/GBC and CR1616 for GBA), the range should be 1 digit over the decimal point.
While both types of battery function the exact same, we do not recommend swapping one for the other since it won’t fit properly in the cart.
3) Connect the terminals of the multimeter to the battery ends (red for positive +, black for negative -).
The positive end is usually under the battery, and the negative end is usually on top. We can also see the (+) and (–) marks on the game cart.
4) Examine the value.
Anything below 1.5V is dangerously low and you should back up your save immediately and swap the battery with a new one. If the multimeter reads a negative value, then most likely the terminals are placed opposite, so switch them around and check the resulted value once more.