109 is connected to the load control ld of counters 95 96 if line 109 is high the outputs a0 a5 of counters 95 96 are set to the values on the a d inputs thereof inputs a d of counter 96 are grounded as are inputs c d of counter 95 inputs a b of counter 95 are supplied by outputs 1y 2y of a data selector 110 data selector 110 is controlled by line 111 to select for outputs 1y 2y the data on inputs 1a 2a if line 111 is low or the data on inputs 1b 2b if line 111 is high outputs a4 and a5 of counter 95 are combined in an and gate 112 to provide a4 a5 as the d input of flip flop 106 outputs a0 a3 of counter 96 are combined in a nor gate 113 to provide a0 a1 a2 a3 39 a0 a1 a2 a3 outputs a4 a5 qc qd of counter 95 are combined in a nor gate 114 to provide a4 a5 qc qd 39 a4 a5 qc qd the outputs of gates 113 and 114 are combined in and gate 115 to provide on line 116 a0 a1 a2 a3 a4 a5 qc qd thus all outputs a0 a5 qc qd of counters 95 96 must be low for line 116 to be high at start up all outputs of counters 95 96 are low line 116 will be high and the output of the inverted q output of flip flop 103 will be.