Singly-key type code inputting method

Abstract

A single-key type cipher inputting method comprises: 1, outputting a special pulse signal to a cipher output port when a cipher input validation port of a controller receives a cipher input starting command, monitoring a level of the cipher input validation port, and recording current pulse transmitting number; 2, the controller dedermining the current pulse number as a bit of cipher to be inputted when the cipher input validation port of the controller monitors a effective validation command during transmission, and storing result in an appointed memory; 3, if bits of the cipher is more than one, the controller continuously outputting the special pulse signal to the cipher output port after the controller validates that the command is finished, and monitoring the level of the cipher input validation port, and recording the pulse transmitting number; then repeating the second step till all bits of the cipher are inputted; when limited time is exceeded, the controller stops to transmite the pulse signal.

Description

technical field [0001] The invention relates to a password input method, in particular to a single-key password input method. Background technique [0002] At present, the commonly used access control electronic anti-theft all adopts the IC card mode, but if the IC card breaks down, you need to enter a specific password to open the door. Although the usual key mode is simple to implement, there is a decoding circuit, and Will occupy more pins, so the implementation cost is relatively high. In addition, if the password judgment device itself performs many tasks and the hardware resources are extremely limited, allocating too many hardware resources to the realization of the password input function will bring great difficulties to hardware cost control. Contents of the invention [0003] The purpose of the present invention is to provide a very low-cost single-key password input method and a realization circuit. During the password input process, the password input judging...

AI Technical Summary

Problems solved by technology

[0002] At present, the commonly used access control electronic anti-theft all adopts the IC card mode, but if the IC card breaks down, you need to enter a specific password to open the door. Although the usual key mode is simple to implement, there is a decoding circuit, and Will occupy more pins, so the implementation cost is relatively high

In addition, if the password judgment device itself performs many tasks and the hardware resources are extremely limited, allocating too many hardware resources to the realization of the password input function will bring great difficulties to hardware cost control

Images