Patent ID: 8073989
Filing Date: 2011-12-06
Classification: G01R,G06F

Abstract:
1. A printer interface detection device for simulating a printer to detect whether a printing function of a printer interface of a computer connected to the printer interface detection device is normal, the printer interface detection device comprising: a printer interface to be connected to the printer interface of the computer, the printer interface comprising a plurality of input/output (I/O) pins and a data signal pin; a microcontroller comprising a plurality of I/O pins to connect with the corresponding I/O pins and the data signal pin of the printer interface, to output a plurality of printing status signals to the computer; an indicator connected to one of the plurality of I/O pins of the microcontroller; a first light emitting diode (LED) displaying a power status of the printer interface detection device, the first LED comprising an anode connected to a power pin of the microcontroller, and a cathode grounded; and a second LED displaying a printing status of the printer interface detection device, the second LED comprising an anode connected to the microcontroller, and a grounded cathode; wherein the microcontroller outputs the plurality of printing status signals to the computer via the corresponding I/O pins according to instructions transmitted by the computer, the computer comparing whether the plurality of printing status signals output by the microcontroller is consistent with printing status signals stored in the computer, to determine whether the printing function of the printer interface of the computer is normal, whereby when the plurality of printing status signals output by the microcontroller is consistent with the printing status signals stored in the computer, the printing function of the printer interface of the computer is normal, and the indicator is lit; wherein the plurality of printing status signals comprises first to fourth printing status signals, the plurality of I/O pins of the printer interface comprises an initialization signal pin, an acknowledgement signal pin, a busy signal pin, a strobe signal pin, and a data signal pin, wherein the acknowledgement signal pin, the busy signal pin, and the strobe signal pin are operable to be triggered at a low level, to output the first to fourth printing status signals, respectively; wherein the microcontroller outputs a low level signal, as the first printing status signal, to the computer via the strobe signal pin of the printer interface detection device, in response to the computer transmitting a printing demand instruction to the microcontroller via the data signal pin; the microcontroller outputs a low level signal, as the second printing status signal, to the computer via the acknowledgement signal pin, in response to the microcontroller receiving print data from the computer; the microcontroller outputs a low level signal, as the third printing status signal, to the computer via the busy signal pin of the printer interface detection device, in response to the controller finishing receiving the print data and the microcontroller outputs a low level signal, as the fourth printing status signal, to the computer via the initialization signal pin, in response to the printer interface detection device finishing printing; wherein when the printer interface detection device has started receiving the print data, the microcontroller outputs a high level signal to turn on the second LED; and when the printer interface detection device has finished printing, the microcontroller outputs a low level signal to turn off the second LED.