| 摘要 |
In devices in which the output signals of a pull-through card reader are to be stored by means of a microcomputer, the problem occurs that there is no direct relationship between the clock pulses stored on the magnetic card and the interrogation cycles of the microcomputer. The device is intended to provide for reliable reading-in of the signals output by the pull-through card reader independently of the speed of pulling-through of the magnetic card and with little circuit complexity. Between the outputs of the pull-through card reader (DKL) and the microcomputer (CPU), an interface is connected which contains a first D-type flipflop (FF1.1) and a second D-type flipflop (FF1.2) for each track of the magnetic card (M). In the first D-type flipflop, the data (DP1) are temporarily stored whilst the second D-type flipflop is used for enabling data transfer in the microcomputer. The device is particularly suitable for transmitting digital data via telephone lines, for example for driving the central computer of a credit card institute by means of a magnetic card from a telephone set. <IMAGE>
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