A circuit capable of reading an input from a device on one pin of an integrated circuit package during one time period and either writing data to another device or reading an input from the other device through the same pin during another time period. In one exemplary implementation in which the one pin is used to write data to the other device, the circuit may sense when data is not being written and change the function of the one pin from that of an output pin to that of an input pin until such time as further data is to be written.