c - 使用 C 编程禁用 arduino 微 Controller 上的键盘

Question

我们有一个原型(prototype)，可以将大钞票变成小钞票。我们使用的是带有键盘的arduino微 Controller ，用户应该按下键盘上的“0”按钮以便机器开始交易。用户可以输入一个值来选择其面额类型。例如，如果您将一张 100 美元的钞票插入机器中，用户可以选择是否要将其作为两张 50 美元的钞票或五张 20 美元的钞票。

我们原型(prototype)的问题是，当机器检测到一笔交易没有钱了时，用户仍然可以使用机器进行另一笔交易。如果您随机按下所有键，我们的编码中存在一个“错误”。用户可以按“0”开始交易。如果机器检测到没有剩余资金可用于另一笔交易，我们希望禁用键盘。

以下是机器检测到没有账单时的代码。如果没有账单，它还会通知业主。

void SupChkU(){
    sLBill5H = digitalRead(LBill5H);
    if (sLBill5H == HIGH){
        lcd.setCursor(0, 0);
        lcd.print("Low in resources");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        delay(100);
        Serial.println("500 Bills is empty ");
        if (SLvlBill5H == false){
            SLvlBill5H = true;
            textForSMS = "500 Bills is empty, please refill ";
            sendSMS(textForSMS);
        }  
        readkeyboard();
        if (keypressed == 11){
            RefillS();
        }  
    }

    sLBill1H = digitalRead(LBill1H);
    if (sLBill1H == HIGH){
        lcd.setCursor(0, 0);
        lcd.print("Low in resources");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        delay(100);
        Serial.println("100 Bills is empty ");
        if (SLvlBill1H == false){
            SLvlBill1H = true;
            textForSMS = "100 Bills is empty, please refill ";
            sendSMS(textForSMS);
        }  
        readkeyboard();
        if (keypressed == 11){
            RefillS();
        }  
    }

    sLBill50 = digitalRead(LBill50);
    if (sLBill50 == HIGH){
        lcd.setCursor(0, 0);
        lcd.print("Low in resources");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        delay(100);
        Serial.println("50 Bills is empty ");
        if (SLvlBill50 == false){
            SLvlBill50 = true;
            textForSMS = "50 Bills is empty, please refill ";
            sendSMS(textForSMS);
        }  
        readkeyboard();
        if (keypressed == 11){
            RefillS();
        }  
    }

    if (CntB5H < 10){
        lcd.setCursor(0, 0);
        lcd.print("Low in resources");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        delay(100);
        Serial.println("PhP 500 Bills Low Level");
        if (SLvlBill5H == false){
            SLvlBill5H = true;
            textForSMS = " Low Level on PhP 500 Bills, please refill ";
            sendSMS(textForSMS);
        }  
        readkeyboard();
        if (keypressed == 11){
            RefillS();
        }
    }

    if (CntB1H < 10){
        lcd.setCursor(0, 0);
        lcd.print("Low in resources");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        delay(100);
        Serial.println("PhP 100 Bills Low Level");
        if (SLvlBill1H == false){
            SLvlBill1H = true;
            textForSMS = " Low Level on PhP 100 Bills, please refill ";
            sendSMS(textForSMS);
        }  
        readkeyboard();
        if (keypressed == 11){
            RefillS();
        }
    }

    if (CntB50 < 10){
        lcd.setCursor(0, 0);
        lcd.print("Low in resources");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        delay(100);
        Serial.println("PhP 50 Bills Low Level");
        if (SLvlBill50 == false){
            SLvlBill50 = true;
            textForSMS = " Low Level on PhP 50 Bills, please refill ";
            sendSMS(textForSMS);
        }  
        readkeyboard();
        if (keypressed == 11){
            RefillS();
        }
    }

    sLCoin1 = digitalRead(LCoin1); 
    if (sLCoin1 == HIGH){
        LvlC1 = true;
        lcd.setCursor(0, 0);
        lcd.print("Low for 1 Peso  ");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        Serial.println(" Low Level for 1 Peso Bin ");
        delay(1000);
        if (SLvlC1 == false){
            SLvlC1 = true;
            textForSMS = " Low Level for 1 Peso Bin ";
            sendSMS(textForSMS);
        }  
    }
    if (sLCoin1 == LOW){
        SLvlC1 = false;
    }   

    sLCoin5 = digitalRead(LCoin5); 
    if (sLCoin5 == HIGH){
        LvlC5 = true;
        lcd.setCursor(0, 0);
        lcd.print("Low for 5 Peso  ");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        Serial.println(" Low Level for 5 Peso Bin ");
        delay(1000);
        if (SLvlC5 == false){
            SLvlC5 = true;
            textForSMS = " Low Level for 5 Peso Bin ";
            sendSMS(textForSMS);
        }  
    }
    if (sLCoin5 == LOW){
        SLvlC5 = false;
    }

    sLCoin10 = digitalRead(LCoin10); 
    if (sLCoin10 == HIGH){
        LvlC10 = true;
        lcd.setCursor(0, 0);
        lcd.print("Low for 10 Peso ");
        lcd.setCursor(0, 1);
        lcd.print("Please see owner");
        Serial.println(" Low Level for 10 Peso Bin ");
        delay(1000);
        if (SLvlC10 == false){
            SLvlC10 = true;
            textForSMS = " Low Level for 10 Peso Bin ";
            sendSMS(textForSMS);
        }  
    }    
    if (sLCoin10 == LOW){
        SLvlC10 = false;
    }
}  

Answer 1

如果键盘连接在 SPI(MISO、MOSI、SCK，...)( https://de.wikipedia.org/wiki/Serial_Peripheral_Interface )上，您可以通过禁用接口(interface)来禁用它:

1) 将 PRR(节能寄存器)中的 PRSPI (?) 位设置为“1”

2) 取消设置(设置“0”)SPCR 寄存器(？)(SPI 控制寄存器)中的 SPE 位(SPI 启用)

请参阅处理器的数据表，也许寄存器和位命名有所不同

如果键盘连接在 UART 上，同样的方法(禁用接口(interface))也适用，...