Digitaler Impulsfolgenteiler mit optimaler Gleichverteilung der aus einer aequidistanten Eingangsimpulsfolge ausgewaehlten Impulse einer Ausgangsimpulsfolge

摘要

1307929 Pulse dividers SIEMENS AG 23 Nov 1970 [22 Nov 1969] 55677/70 Headings G4D D7X D6Y D6C1 and D6C2 Using an algarithm involving only addition, subtraction and comparison operations, a train of N input pulses is converted to a train of n output pulses such that N/n = a + Z/N1, where a is an integer and Z/N1 is a proper fraction, the output pulses being as uniformly distributed as possible, i.e. occurring every a or (a + 1) input pulses. Operation.-(i) N1 is entered in a store S3, Fig. 2, through gates U1 and O1; (ii) gates U2 and U3 are opened so that parallel adder PA performs the subtraction (S3 - 2Z) (the complement of 2Z being held in store S2); (iii) S3 is reset; (iv) the result in PA is passed through U4 and O1 into S3; (v) PA is reset; (vi) the sign bit A in S3 indicating whether the fraction Z/N1 is greater than ¢ or less - than/equal to ¢ is applied at E R , Fig. 3, to produce an output pulse from Un after (a + 1) or a pulses respectively of the input train E n have been applied to a backward counter Rz pre-set by store S4 to (a + 1); (vii) the output pulse pre-sets R Z again via gates U 0 -U m , and via input R, Fig. 2, causes entry of the contents of S3 and S1 (= 2N1) or S3 alone into PA depending on whether it has occurred after (a + 1) or a input pulses respectively: (viii) S3 is reset; (ix) the result from PA is entered in S3; (x) PA is reset; (xi) steps (ii) to (x) are repeated. The sign bit of the result of the operations (S3 - 2Z) and (S 3 + 2N1) indicates whether the fraction Z/N1 is greater than or less than/equal to successively decreasing or increasing fractions. After N input pulses during' which the n output pulses are produced, the contents of S3 are again equal to N1 and the entire cycle repeats for the next N input pulses.