| 摘要 |
PROBLEM TO BE SOLVED: To reduce the number of signal lines and cope with increase of batteries by stipulating the turning on/off state of a switch, only by the contents of serial data. SOLUTION: An auxiliary electrode 1 has a CPU substrate 2, control object substrates 31-34 and a battery group 9. Data showing that any switch is designated and turned on out of switches which are arranged in relays 71-74 and connected with the respective batteries of the battery group 9 are transferred as serial data between control object substrate 31-34. As compared with the conventional case where data like the above data are transferred as parallel data, the number of signal lines can be reduced. When the number of batteries is increased, since the number of the control object substrate 31-34 is increased in order to correspond to the batteries, it is not necessary to increase the number of signal lines in the control object substrate 31-34 or to change circuit design as in the conventional cases, so that it is easy to cope with the increase in the number of batteries. |
