I would like to program several (exactly four) microcontrollers LPC1114 in the same circuit using the SWD interface. I have a circuit in which the lines: 3V3, GND, SWDIO and SWCLK are connected parallel to the microcontroller's pins and I am going to choose one of the line to control the programming process. In this case that line would be disconnected (using a relay) to the all microcontrollers and we want to connect the line just to the one of the microcontrollers, which we want to program at a given time. The other lines are connected parallel to the all microcontrollers all the time. Now there is my question: which line - 3V3, GND, SWDIO or SWCLK - is the best to use to choose the microcontoller which is going to be programmed?