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使用基于74HC32和STM32F302VC的2x2键盘管理多个功能

掌控您的控制:4个按钮,1个解决方案

2x2 Key Click with CLICKER 4 for STM32F302VCT6

已发布 7月 22, 2025

点击板

2x2 Key Click

开发板

CLICKER 4 for STM32F302VCT6

编译器

NECTO Studio

微控制器单元

STM32F302VC

我们的目标是通过我们的4合1按钮集成最大化功能,同时最小化复杂性。

A

A

硬件概览

它是如何工作的?

2x2 Key Click基于带有去抖动电路的2x2按钮键盘,由Nexperia的四输入OR门74HC32和德州仪器的六输入施密特触发器倒置器SN74HC14组成。在电子学中,当两个金属组件接触时(就像按下按钮时),它们会反弹或产生多个信号,直到它们达到稳定状态。您希望单个接触被记录,但微控制器将此记录为按下按钮多次。因此,去除反弹或低高电压的尖峰就是所谓的去抖动。从图形上来说,您希

望有一条清晰的线,而不是尖峰。去抖动电路确保输出上没有电压变化。多亏了它,一个按钮按下就被记录下来。所有四个施密特触发器输出都连接到逻辑OR门74HC32的输入引脚,其输出直接连接到mikroBUS上的INT引脚。此引脚用于在按下按钮时向MCU发出中断信号。这样,MCU软件可以实现为简单的轮询例程,而不需要在代码中编程延迟(如果没有硬件去抖动电路存在,这将是必要的)。

多亏了INT引脚,您可以轻松地编写一个通用的中断服务例程,以检测按钮何时被按下(按钮状态从低逻辑电平变为高逻辑电平)。此Click板™可以使用PWR SEL跳线选择3.3V或5V逻辑电压电平操作。这样,既可以使3.3V又可以使5V能力的MCU正常使用通信线路。此外,此Click板™配备了一个包含易于使用的功能和示例代码的库,可用作进一步开发的参考。

2x2 Key Click top side image
2x2 Key Click bottom side image

功能概述

开发板

Clicker 4 for STM32F3 是一款紧凑型开发板,作为完整的解决方案而设计,可帮助用户快速构建具备独特功能的定制设备。该板搭载 STMicroelectronics 的 STM32F302VCT6 微控制器,配备四个 mikroBUS™ 插槽用于连接 Click boards™、完善的电源管理功能以及其他实用资源,是快速开发各类应用的理想平台。其核心 MCU STM32F302VCT6 基于高性能 

Arm® Cortex®-M4 32 位处理器,运行频率高达 168MHz,处理能力强大,能够满足各种高复杂度任务的需求,使 Clicker 4 能灵活适应多种应用场景。除了两个 1x20 引脚排针外,板载最显著的连接特性是四个增强型 mikroBUS™ 插槽,支持接入数量庞大的 Click boards™ 生态系统,该生态每日持续扩展。Clicker 4 各功能区域标识清晰,界面直观简洁,极大

提升使用便捷性和开发效率。Clicker 4 的价值不仅在于加速原型开发与应用构建阶段,更在于其作为独立完整方案可直接集成至实际项目中,无需额外硬件修改。四角各设有直径 4.2mm(0.165")的安装孔,便于通过螺丝轻松固定。对于多数应用,只需配套一个外壳,即可将 Clicker 4 开发板转化为完整、实用且外观精美的定制系统。

CLICKER 4 for STM32F302VCT6 double image

微控制器概述 

MCU卡片 / MCU

STM32F302VC Image

建筑

ARM Cortex-M4

MCU 内存 (KB)

256

硅供应商

STMicroelectronics

引脚数

100

RAM (字节)

40960

使用的MCU引脚

mikroBUS™映射器

T1 Button Status
PC4
AN
T2 Button Status
PC15
RST
T3 Button Status
PA4
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
T4 Button Status
PE9
PWM
Interrupt
PD0
INT
NC
NC
TX
NC
NC
RX
NC
NC
SCL
NC
NC
SDA
Power Supply
5V
5V
Ground
GND
GND
1

“仔细看看!”

Click board™ 原理图

2x2 Key Click Schematic schematic

一步一步来

项目组装

PIC32MZ MXS Data Capture Board front image hardware assembly

从选择您的开发板和Click板™开始。以CLICKER 4 for STM32F302VCT6作为您的开发板开始。

PIC32MZ MXS Data Capture Board front image hardware assembly
Thermo 21 Click front image hardware assembly
Board mapper by product6 hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
Necto image step 5 hardware assembly
Necto image step 6 hardware assembly
PIC32MZ MXS Data Capture Board NECTO MCU Selection Step hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto image step 11 hardware assembly

软件支持

库描述

这个库包含2x2 Key Click驱动的API。

关键函数:

  • c2x2key_t1_state - 此函数获取AN引脚的状态

  • c2x2key_t2_state - 此函数获取RST引脚的状态

  • c2x2key_t3_state - 此函数获取CS引脚的状态

  • c2x2key_t4_state - 此函数获取PWM引脚的状态

开源

代码示例

完整的应用程序代码和一个现成的项目可以通过NECTO Studio包管理器直接安装到NECTO Studio 应用程序代码也可以在MIKROE的GitHub账户中找到。

/*!
 * \file 
 * \brief 2x2 key Click example
 * 
 * # Description
 * 2x2 Key Click has a 4 button keypad and allows multiple key presses.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Application Init performs Logger and Click initialization.
 * 
 * ## Application Task  
 * This example code demonstrates the usage of 2X2 Key Click board.
 * Detects whether any of the keys is pressed where results are being sent 
 * to the UART terminal where you can track changes.
 * 
 * \author Mihajlo Djordjevic
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "c2x2key.h"

uint8_t t1_state     = 0;
uint8_t t1_state_old = 1;
uint8_t t2_state     = 0;
uint8_t t2_state_old = 1;
uint8_t t3_state     = 0;
uint8_t t3_state_old = 1;
uint8_t t4_state     = 0;
uint8_t t4_state_old = 1;

// ------------------------------------------------------------------ VARIABLES

static c2x2key_t c2x2key;
static log_t logger;

// ------------------------------------------------------- ADDITIONAL FUNCTIONS


// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    c2x2key_cfg_t cfg;

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_printf( &logger, "-- Application  Init --\r\n" );
    Delay_ms ( 1000 );

    //  Click initialization.

    c2x2key_cfg_setup( &cfg );
    C2X2KEY_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    c2x2key_init( &c2x2key, &cfg );
    
    log_printf( &logger, "-----------------------\r\n" );
    log_printf( &logger, "     2X2 key Click     \r\n" );
    log_printf( &logger, "-----------------------\r\n" );
    Delay_ms ( 1000 );
    
    log_printf( &logger, "    System is ready    \r\n" );
    log_printf( &logger, "-----------------------\r\n" );
    Delay_ms ( 1000 );
}

void application_task ( void )
{
   t1_state = c2x2key_t1_state( &c2x2key );
   
   if ( ( t1_state == 1 ) && ( t1_state_old == 0 ) )
    {
        log_printf( &logger, "-----------------------\r\n" );
        log_printf( &logger, "     Key 1 pressed     \r\n" );
        log_printf( &logger, "-----------------------\r\n" );
        t1_state_old = 1;
    }
    
    if ( ( t1_state == 0 ) && ( t1_state_old == 1 ) )
    {
        t1_state_old = 0;
    }
    
    t2_state = c2x2key_t2_state( &c2x2key );
   
   if ( ( t2_state == 1 ) && ( t2_state_old == 0 ) )
    {
        log_printf( &logger, "-----------------------\r\n" );
        log_printf( &logger, "     Key 2 pressed     \r\n" );
        log_printf( &logger, "-----------------------\r\n" );
        t2_state_old = 1;
    }
    
    if ( ( t2_state == 0 ) && ( t2_state_old == 1 ) )
    {
        t2_state_old = 0;
    }
    
    t3_state = c2x2key_t3_state( &c2x2key );
   
   if ( ( t3_state == 1 ) && ( t3_state_old == 0 ) )
    {
        log_printf( &logger, "-----------------------\r\n" );
        log_printf( &logger, "     Key 3 pressed     \r\n" );
        log_printf( &logger, "-----------------------\r\n" );
        t3_state_old = 1;
    }
    
    if ( ( t3_state == 0 ) && ( t3_state_old == 1 ) )
    {
        t3_state_old = 0;
    }
    
    t4_state = c2x2key_t4_state( &c2x2key );
   
   if ( ( t4_state == 1 ) && ( t4_state_old == 0 ) )
    {
        log_printf( &logger, "-----------------------\r\n" );
        log_printf( &logger, "     Key 4 pressed     \r\n" );
        log_printf( &logger, "-----------------------\r\n" );
        t4_state_old = 1;
    }
    
    if ( ( t4_state == 0 ) && ( t4_state_old == 1 ) )
    {
        t4_state_old = 0;
    }
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

// ------------------------------------------------------------------------ END

额外支持

资源

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