U盘数据采集系统软件篇一（串口和矩阵键盘模块）
时间：2021-01-21 01:02:23
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[导读]硬件设计完成，下面就要进行软件开发了，本篇主要介绍串口模块、按键模块的初始化及功能测试。
文 | 嵌Sir
硬件设计完成，下面就要进行软件开发了，本篇主要介绍串口模块、按键模块的初始化及功能测试。
程序开发前我习惯查看原理图把所有外设对应的管脚全部列出来，方便后续开发时查看。
01
串口模块
串口管脚配置如下：
查看芯片规格书可知 PA9和PA10的默认功能为串口1，PD8和PD9需要重定义为串口3使用。
管脚定义:
本文使用中断方式接收和发送，串口和串口中断初始化代码如下：
GPIO_InitTypeDef GPIO_InitStructure;USART_InitTypeDef USART_InitStructure;NVIC_InitTypeDef NVIC_InitStructure; //UART1 管脚配置：时钟、模式 RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE); GPIO_InitStructure.GPIO_Pin = UART1_RXD_GPIO_PIN;GPIO_InitStructure.GPIO_Mode = UART1_RXD_GPIO_MODE; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz; GPIO_Init(UART1_RXD_GPIO_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = UART1_TXD_GPIO_PIN;GPIO_InitStructure.GPIO_Mode = UART1_TXD_GPIO_MODE; GPIO_Init(UART1_TXD_GPIO_PORT, &GPIO_InitStructure); USART_InitStructure.USART_BaudRate = 9600;USART_InitStructure.USART_WordLength = USART_WordLength_8b;USART_InitStructure.USART_StopBits = USART_StopBits_1;USART_InitStructure.USART_Parity = USART_Parity_No;USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; USART_Init(USART1, &USART_InitStructure); //配置nvic向量表NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); /* Enable the USARTy Interrupt */NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_Init(&NVIC_InitStructure); /* Enable USART1 Receive and Transmit interrupts */USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);USART_ITConfig(USART1, USART_IT_TXE, DISABLE); //一开始就是要关闭 /* Enable USART */USART_Cmd(USART1, ENABLE); gb_needDealUart1Data = 0;uart1DelayTimer = 0; RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);GPIO_PinRemapConfig(GPIO_FullRemap_USART3, ENABLE);//UART3 管脚配置：时钟、模式 GPIO_InitStructure.GPIO_Pin = UART3_RXD_GPIO_PIN;GPIO_InitStructure.GPIO_Mode = UART3_RXD_GPIO_MODE; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz; GPIO_Init(UART3_RXD_GPIO_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = UART3_TXD_GPIO_PIN;GPIO_InitStructure.GPIO_Mode = UART3_TXD_GPIO_MODE; GPIO_Init(UART3_TXD_GPIO_PORT, &GPIO_InitStructure); USART_InitStructure.USART_BaudRate = 115200;USART_InitStructure.USART_WordLength = USART_WordLength_8b;USART_InitStructure.USART_StopBits = USART_StopBits_1;USART_InitStructure.USART_Parity = USART_Parity_No;USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; USART_Init(USART3, &USART_InitStructure); //配置nvic向量表NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); /* Enable the USARTy Interrupt */NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_Init(&NVIC_InitStructure); /* Enable USART3 Receive and Transmit interrupts */USART_ITConfig(USART3, USART_IT_RXNE, ENABLE);USART_ITConfig(USART3, USART_IT_TXE, DISABLE); //一开始就是要关闭 /* Enable USART */USART_Cmd(USART3, ENABLE); gb_needDealUart3Data = 0;
初始化的时候别忘记串口3的remap。
GPIO_PinRemapConfig(GPIO_FullRemap_USART3, ENABLE);
串口收发中断处理，以串口3为例：
void USART3_IRQHandler(void){ u8 d; if (USART_GetFlagStatus(USART3, USART_FLAG_RXNE)) { /* Read one byte from the receive data register */ d = USART_ReceiveData(USART3); uart3infifo_DataIn(d); uart3DelayTimer = UART3_DATA_DELAY; gb_needDealUart3Data = 0; } else if (USART_GetFlagStatus(USART3, USART_FLAG_TXE)) { if (uart3outfifo_count > 0) { /* Write one b yte to the transmit data register */ USART_SendData(USART3, uart3outfifo_DataOut()); //顺便清除flag_TXE } else { /* Disable the USARTy Transmit interrupt */ USART_ITConfig(USART3, USART_IT_TXE, DISABLE); //实际上，发送为空的标志还在，只是关闭中断 } }}
串口中断中收到数据先进FIFO，等一个数据包接收完后进入处理。需要发送数据，把数据填入fifo，中断里自动发送。我一般都是采用这种中断加fifo的收发方式。中断就像是后台操作一样，在主程序的流程中，不用刻意去关注中断方式发送了没有，何时接收等，而查询方式是在主程序流程中不断查看是否接收到了数据，一般用while不断循环查看。中断方式可以更高效利用CPU ，节省CPU的时间，查询就会增加CPU负担。
02
按键模块
查看原理图，矩阵按键管脚如下：
矩阵键盘管脚定义及初始化：
void keyboard_Init(void){ GPIO_InitTypeDef GPIO_InitStructure; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; GPIO_InitStructure.GPIO_Pin = ROW0_GPIO_PIN; GPIO_InitStructure.GPIO_Mode = ROW0_GPIO_MODE; GPIO_Init(ROW0_GPIO_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = ROW1_GPIO_PIN; GPIO_InitStructure.GPIO_Mode = ROW1_GPIO_MODE; GPIO_Init(ROW1_GPIO_PORT, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = COL0_GPIO_PIN; GPIO_InitStructure.GPIO_Mode = COL0_GPIO_MODE; GPIO_Init(COL0_GPIO_PORT, &GPIO_InitStructure); SetCol(0); GPIO_InitStructure.GPIO_Pin = COL1_GPIO_PIN; GPIO_InitStructure.GPIO_Mode = COL1_GPIO_MODE; GPIO_Init(COL1_GPIO_PORT, &GPIO_InitStructure); SetCol(1);}
矩阵键盘键值读取：
u8 keyboard_GetCurrentKey( void){ u8 kbVal; u8 rowIndex; u8 colIndex; kbVal = KEY_noKey; for(colIndex = 0; colIndex < COL_NUM; colIndex ++)//按列查询 { ClrCol(colIndex);//列线置低 for (rowIndex=0; rowIndex < ROW_NUM; rowIndex ++)//按行扫描 { if (!RowVal(rowIndex))//读当前行电平 { kbVal = KEY_VAL[rowIndex][colIndex];//有值返回，并跳出循环 break; } } SetCol(colIndex);//列线置高 if (kbVal != KEY_noKey) { break; } } return(kbVal);}
可以在主函数中轮询键值进行处理，也可以在定时器中断中轮询键值。在中断中的不要写耗时操作或者加延时。在定时中断轮询键值一般也是配合fifo使用。代码如下：
//2ms定时器void TIM5_IRQHandler(void){ if (TIM_GetFlagStatus(TIM5, TIM_IT_Update)) { TIM_ClearFlag(TIM5, TIM_IT_Update); ScanKeyDown();//处理按键中断 }}
void ScanKeyDown(void){ g_keyPara.currentLcdKey = keyboard_GetCurrentKey(); //读取键值 g_keyPara.keyFlag <<= 1; if(g_keyPara.currentLcdKey != KEY_noKey) { g_keyPara.keyFlag ++; } if (!g_keyPara.longLcdKeyFlag)//长按和短按处理 和短按的去抖处理 { if (g_keyPara.currentLcdKey == KEY_noKey) { if ((g_keyPara.shortLcdKeyTimer == 0)&&g_keyPara.shortLcdKey != 0) { fifo_DataIn(KB_FIFO,g_keyPara.shortLcdKey); //键值进fifo队列等待处理 } g_keyPara.enterLongLcdKeyTimer = ENTER_LONG_KEY_TIME; g_keyPara.shortLcdKeyTimer = SHORT_KEY_TIME; } else { if (g_keyPara.shortLcdKeyTimer > 0) { g_keyPara.shortLcdKeyTimer --; if (g_keyPara.shortLcdKeyTimer == 0) { g_keyPara.shortLcdKey = g_keyPara.currentLcdKey; } } if(g_keyPara.enterLongLcdKeyTimer > 0) { g_keyPara.enterLongLcdKeyTimer --; if (g_keyPara.enterLongLcdKeyTimer == 0) { g_keyPara.longLcdKeyIntervalTimer = LONG_KEY_INTERVAL_TIME; g_keyPara.longLcdKeyFlag = 1; g_keyPara.longLcdKey = g_keyPara.currentLcdKey; fifo_DataIn(KB_FIFO,g_keyPara.longLcdKey+0x20);//键值进fifo队列等待处理 } } } } else { if (g_keyPara.currentLcdKey == g_keyPara.longLcdKey) { if (g_keyPara.longLcdKeyIntervalTimer > 0) { g_keyPara.longLcdKeyIntervalTimer --; if (g_keyPara.longLcdKeyIntervalTimer == 0) { fifo_DataIn(KB_FIFO,g_keyPara.longLcdKey+0x20); //键值进fifo队列等待处理 } } } else { g_keyPara.longLcdKeyFlag = 0; g_keyPara.longLcdKey = KEY_noKey; g_keyPara.shortLcdKey = KEY_noKey; g_keyPara.shortLcdKeyTimer = SHORT_KEY_TIME; g_keyPara.enterLongLcdKeyTimer = ENTER_LONG_KEY_TIME; g_keyPara.longLcdKeyIntervalTimer = LONG_KEY_INTERVAL_TIME; } }}
/ The End /
本文主要介绍了串口模块和矩阵键盘模块的管脚配置和初始化，并简要介绍了各模块的中断使用方法。如有疑问，欢迎留言讨论。
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