Patent GB-1496608-A (GB)
Title: Electronic information processing system
IPC: G06F1/30
Filed: 1975-09-23
Abstract: 1496608 Electronic cash registers OMRON TATEISI ELECTRONICS CO 23 Sept 1975 [25 Sept 74] 38984/75 Heading G4T For each of a series of purchased items, a price and a code (identifying the type of item) are entered into and printed by an electronic cash register, the total price of all items being printed after completion of the entry and printing of all item prices and codes. The invention is concerned with minimizing inconvenience caused by a power supply failure during the above operations and provides means which, upon sensing the restoration of power supply, automatically causes the printing of the data which had just been partially or completely printed when the failure occurred. Fig. 2 embodiment-normal operation. (a) Initially the operator depresses switches 1 and 2 and enters his code number at 3. These operation cause circuit 33 to convert the A.C. supply to D.C. power for the cash register, and cause an enabling signal for the plus/equals key 4 to issue from flip-flop 7 when a counter 9 senses that the requisite number of digits for an operator code have been entered at 3. The entered code itself is verified by means not shown. The output from flip-flop 7 also disables counter 9 and is fed to one input of AND 31. (b) For each item the price is entered at 3 and passes to register 15 via AND 10, enabled by the low level output signal from flip-flop 12 inverted at 13. The output from AND 10 also sets flip-flop 16. Now plus/equals key 4 is depressed to set flip-flop 12, the high level set output of which is inverted at 13 to disable AND 10 and is passed as enabling signals to ANDs 11 and 38. The code of the item is now entered at 3 and passed via AND 11 to non- volatile register 18. When a counter 17 senses that the requisite number of digits for the item code have been entered, it outputs a signal which enables gates 22, 23 (so that the price and code pass from registers 15, 18 to non- votatile registers 25, 27 respectively) and which enables an addition circuit 20 (so that the cumulative total in non-volatile register 26 is added to the amount held in register 15 and the sum loaded into 26) and which passes through an OR 24 (so that printer 32 is enabled to print the price and code). The output from counter 17 also resets flip-flops 16 and 12. (c) After entry of the last item price and code, key 4 is depressed to set flip-flop 12 and, because flip-flop 16 is still reset, AND 14 is enabled. The output from AND 14 passes via OR 21 to printer 32, to cause printing of the total amount held in register 26, and passes to register 18 to clear same. Operation after power failure. Recovery of the power supply is sensed by circuit 29, the output from which resets flipflop 7 and set flip-flop 30. The operator initiates operations (a) above. AND 31 is therefore enabled and its output resets flip-flop 30, instructs the printer to print the word RECOVERED (Fig. 3) alongside any amount now automatically printed, and enables circuit 28. The latter senses whether register 18 is cleared or not (i.e. whether the totalling stage had or had not been reached when the power failure occurred) and accordingly instructs the printer to print either the total from register 26 or the price and code from registers 25 and 27. Modifications. In a first modification (Fig. 2A), when power is restored and circuit 28 senses that register 18 is not clear, the printer automatically prints out not only the price and code from registers 25 and 27, but also the cumulative total from register 26. This prevents confusion when the power failure occurred during the repeated print out of the same price and code (corresponding to several identical items). In a second modification (Fig. 5A), when power is restored and circuit 28 senses that register 18 is not clear, the price and code from registers 25 and 27 are only printed out if the power failure occurred after the completion of the entry at 3 of a particular price and code (i.e. when counter 17 gives an output) and before the completion of the printing of such price and code. In a third modification (Figs. 6 and 7), the output from circuit 29 is led to flip-flop 30 via an AND, which is only enabled when counter 17 outputs its signal (i.e. when an item code has been entered). Thus the output from circuit 29 is not effective when the power is first switched on in the normal way, as opposed to being restored after a failure.