By placing the AND gate, with its inputs on the Q1 and Q2 of the BCD counter of the decades, we make sure that when the gate closes, the RST input of the BCD counter will be set to logical “1”, which on its turn, will force the circuit to start over. The transformed circuit appears in picture 2.
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By placing the AND gate, with its inputs on the Q1 and Q2 of the BCD counter of the decades, we make sure that when the gate closes, the RST input of the BCD counter will be set to logical “1”, which on its turn, will force the circuit to start over. The transformed circuit appears in picture 2.