Information processor

An information processor configured to charge one of a plurality of electronic devices replaceably connected to the information apparatus via a bus comprising a data signal line and a power supply line, when a differential signal pair output to the one of the electronic devices through the data signal line is at or above a predetermined voltage difference, the one of the electronic devices being charged through the power supply line, the information processor comprising:

• an input and output module configured to input and output a data signal through the data signal line;
• a first voltage supply configured to supply a first pair of differential signals comprising a first voltage difference;
• a second voltage supply configured to supply a second pair of differential signals comprising a second voltage difference;
• a first switch configured to select either the first pair of differential signals or the second pair of differential signals, and to use the selected pair as an output in response to a first control signal;
• and
• a second switch configured to receive the output from the first switch as an input, and to output the input to the electronic device through the data signal line in response to a second control signal.