4×4矩阵式键盘识别技术

（1．4×4矩阵键盘识别处理



（2．每个按键有它的行值和列值　，行值和列值的组合就是识别这个按键的编码。矩阵的行线和列线分别通过两并行接口和CPU通信。每个按键的状态同样需变成数字量“0”和“1”，开关的一端（列线）通过电阻接VCC，而接地是通过程序输出数字“0”实现的。键盘处理程序的任务是：确定有无键按下，判断哪一个键按下，键的功能是什么；还要消除按键在闭合或断开时的抖动。两个并行口中，一个输出扫描码，使按键逐行动态接地，另一个并行口输入按键状态，由行扫描值和回馈信号共同形成键编码而识别按键，通过软件查表，查出该键的功能。

-4 × 4 matrix keyboard recognition technology

(1.4 × 4 matrix keyboard recognition processing



　　 (2. Each key has its row value and column value, the value and the value of the portfolio is set out to identify the key number. Matrix line line line and out through the two parallel CPU interface and communications. The state of each key the same need to become a digital "0" and "1", switch on one end (line out) then through the resistor VCC, and ground through the output number "0" to achieve. keyboard processing task is to: determine whether the key pressed to determine which key to press, what key features　would also like to eliminate the disconnect button when in the closed or jitter. two parallel population, a key scan output, so that key dynamic grounding line, and the other parallel port input keys, and by the line scan values and the formation of a common feedback signal coding and identification of key buttons, through the software look-up table for identifying the key fu