Elektronisches Eingang/Ausgang-Verarbeitungsgerät mit Überwachung der Versorgungsspannung

摘要

An electronic apparatus which does not become inoperative due to a voltage drop during the inputting or outputting of data. The apparatus includes an analog-to-digital converter for measuring the voltage output from a power source and for inputting the voltage to a central processing unit and a control section so that during output of test data to a parallel port before substantial data is output, the voltage output from the power source is measured, and a value for the minimum voltage of the power source is stored. When the minimum supply voltage during the output of the test data is lower than a reference voltage, actual data output is inhibited, thereby preventing the apparatus from becoming inoperative during data output. The minimum voltage output from the power source can be intermittently detected by a timer interrupt procedure. In the configuration, the minimum main supply voltage is compared with the predetermined reference voltage during data input/output so that a voltage drop is detected during data input/output, and data input/output processing is restricted according to the results of detection.