DEVICE FOR A MICRO-PROGRAMMING CONTROL OF ELECTRONIC CASH REGISTERS

摘要

1457446 Microprogrammed cash register DSO "IZOT" 10 Dec 1973 [10 Dec 1972] 57199/73 Heading G4A A microprogram controlled cash register has a magnetic core store providing both working and microprogram storage and a data preservation device activated in response to faults. The core store 1 is arbitrarily divided into two parts storing working data and microprograms, the parts being addressed by a microprogram address counter 3 and an address register 9 in conjunction with an access device 4, the data &c. being read out into register 8. Instructions are fed in via a keyboard input device 19 and are executed by a corresponding microprogram. Six microprogram control registers 10-15 are connected as shown with a microcommand decoder 2, a binary/binary-decimal arithmetic unit 17 (binary for microcommands and binary-decimal for data) and a comparator 16. The system also includes a printer 21, display 22, and a transfer device 18, e.g. for connection to a remote processor. A sensor 6 detects faults, e.g. power failure or excessive temperature, and causes an "interrupt" microprogram to be activated to store the address counter and various other register contents and to switch off various supply voltages in a fixed sequence, the power for this purpose being derived in the case of a power failure from the energy stores within the system. When the power is restored or the system is otherwise switched on the system is reactivated, the voltage supplies being switched on in the correct sequence, controlling timing oscillator 7 being activated, and the various register contents restored to allow the operation to continue from the point of interruption.