I am very unfamiliar with the propagation of data with Bluetooth low energy (BLE) but I remember reading somewhere that it can only accept char values.
At the moment, my project makes use of a ACS 711 hall effect current sensor to monitor current being provided to or from a battery every 30 seconds. Now I would like to store the positive current values when the battery charges into a float type variable that constantly increments itself by each new charging current value and be able to send that to a phone app via Bluetooth.
I understand that I am going to need storage since this number is only going to get larger past the memory limit available by the Arduino nano.
My question is how would I go about doing all this sensibly? Should it be best to be doing the arithmetic on back end framework of the app and just have the app receive char data constantly every 30 seconds?
Should I implement an SD card so that I can write this large variable into it with the BLE just sending the last generated current charging variable to my app?
Any insight on code implementation or storage ideas would be greatly appreciated.