{HEAD ~ a microprocessor} connected to the battery through {TAIL ~ a regulator} to obtain a suitable DC voltage, the power supply switch and the illumination switch 
connected through
{ HEAD ~ a microprocessor } connected to the battery through { TAIL ~ a regulator } to obtain a suitable DC voltage , the power supply switch and the illumination switch
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH