After the switch of number 3 is closed, the switch of number 9 will inevitably confuse the program. At this time, the system will clear the value of data register D0 and start the alarm program.
After the switch of the number 3 is closed, the number 9 switch is closed again and the program is bound to be confused. At this point, the system zeros the value of the data register D0 and turns on the alarm program.
After the switch of number 3 is closed, the switch of number 9 will make the program confused. At this time, the system will clear the value of data register d0 and start the alarm program.