Schematic

reskey_sch.pdf

The schematic introduces a classic configuration of dial gauge inputs in order to find the value of the 3 Resistances. In fact all it is based on the loading time of the C7 condenser (that in fact it is a NPO) that it is directly proportional to the value of the Resistances present on the Key. This Resistive Code will be saved in the memory EEPROM 24C01