Rechenmaschine

摘要

An electronic calculating machine with two multistage registers and with circuitry controlled by an interchange function key on a keyboard are used to interchange the corresponding digit denominations of the numbers stored in the two registers. The interchange of each digit denomination is a two-part operation. In the first part a first pulse train is used to simultaneously circulate the digits in the corresponding denomination of the registers in order to store in a counter circuit a difference pulse count equal to the difference between the digits and to obtain a signal whose polarity is dependent upon which register has the larger digit. In the second part the difference pulse count and the polarity of the signal are used during the second pulse train to control the entry of part of the second pulse train to the one register and then to control the entry of the rest of the second pulse train to the other register so as to interchange the corresponding digits.