To perform bidirectional recording accurately by providing means for measuring the time being elapsed after a control signal is further inverted before the recorder body recognizes variation in a response signal being outputted from a position detecting means thereby recognizing the error of printing position accurately for each recorder.

The recorder comprises an HP sensor 8 for detecting the home position of a carriage 30, and a printer controller 1 for driving the HP sensor 8 and measuring the time required for turning it on/off (the time to be elapsed before the recorder recognizes variation of a on/off control signal after it is varied). According to the arrangement, error of printing position can be recognized accurately for each recorder. Since the error of printing position in bidirectional recording is corrected based on the difference of time measured by the printer controller 1, bidirectional recording can be carried out accurately.