【LPC1768-DEV】⑤读按键值

yinwuqing · 发表于 2019-3-31 22:13:31

本帖最后由 yinwuqing 于 2019-3-31 22:17 编辑

今天既是周末，也是月末。时间过得好快，平时工作比较忙，上班也是六休一，因此只有挤挤周末的时间来研究研究LPC1768这款工业级开发板。我们从之前的宝马LPC1768资料库中以及@管管给我们的sdk资料，我们可以得知按键板是使用PCA9555的i2c与LPC1768通信的。
IRD Keypad.png

原理图如下：

其实现的原理如下：

按键时的结构映射如下图所示：
Keypad结构映射.png

按键解码的流程图如下所示：
解码流程.png

跟之前操作一样，新建一个工程，然后将微控制器软件接口标准库（CMSIS）勾选好。并在“RTE_Device.h”头文件中使能I2C接口。按键的键值可以在头文件的宏定义中自定义，工程中大部分代码如下：

#include "LPC17xx.h" /* LPC17xx Definitions */
#include "GPIO_LPC17xx.h"
#include "PIN_LPC17xx.h"
#include "UART_LPC17xx.h"
#include "I2C_LPC17xx.h"
#include <string.h>
#include <stdio.h>
#include "keypad.h"
typedef unsigned char UCHAR;
UCHAR Key_Flag;
UCHAR I2C_Read_Counter = 0;
UCHAR I2C_Write_Counter = 0;
UCHAR Keypad_Data_Read;
UCHAR Column_Value = 0;
UCHAR Row_Counter=0;
UCHAR Row_Found = 0;
UCHAR Row_Value;
UCHAR Brightness_Global=8;
UCHAR I2C_Data_Read_Buffer[2];
UCHAR I2C_Data_Write_Buffer[2];
#define INTERNAL 0
#define EXTERNAL 1
#define KPAD_NB_ROW 6
#define KPAD_NB_COLUMN 6
/*Keypad defines*/
#define P1_KPAD_COLUMN 0x3F // 6 columns P1[0] to P1[5]
#define P1_KPAD_COLUMN_MASK 0xC0
#define P1_KPAD_ROW_OUT_REG 0xC0 // column configured as output
#define P0_KPAD_ROW 0x3F // 6 rows P0[0] to P0[5]
#define P0_6_BACKLIGHT 0x40 // P0[6] used for backlight control
#define P0_6_BACKLIGHT_OUT_REG 0xBF // P0[6] configured as output
#define P0_7_LED 0x80 // P0[7] used for LED control
#define P0_7_LED_OUT_REG 0x7F // P0[7] configured as output
#define P1_7_6_LED 0xC0 // P1[7:6] used for LED control
#define P1_7_6_LED_OUT_REG 0x3F // P1[7:6] configured as output
/*---------------------------------------------------------------------------*
* Constants & Macros:
*---------------------------------------------------------------------------*/
#define INSTR_CLEAR 0x01 // 1.53 ms
#define INSTR_RETURN_HOME(settings) 0x02 // 1.53 ms
#define INSTR_ENTRY_MODE(settings) (0x06|(settings)) // 39 uS
#define IENTRY_INCREMENT (1<<1)
#define IENTRY_DECREMENT (0<<1)
#define IENTRY_SHIFT_ON (1<<0)
#define IENTRY_SHIFT_OFF (0<<0)
#define INSTR_DISPLAY(settings) (0x08|(settings)) // 39 uS
#define IDISPLAY_ON (1<<2)
#define IDISPLAY_OFF (0<<2)
#define IDISPLAY_CURSOR_ON (1<<1)
#define IDISPLAY_CURSOR_OFF (0<<1)
#define IDISPLAY_BLINK_ON (1<<0)
#define IDISPLAY_BLINK_OFF (0<<0)
#define INSTR_SHIFT(settings) (0x10|(settings)) // 39 uS
#define ISHIFT_SCREEN (1<<3)
#define ISHIFT_CURSOR (0<<3)
#define ISHIFT_RIGHT (1<<2)
#define ISHIFT_LEFT (0<<2)
#define INSTR_FUNC(settings) (0x20|(settings)) // 39 uS
#define IFUNC_8BIT (1<<4)
#define IFUNC_4BIT (0<<4)
#define IFUNC_TWO_LINE (1<<3)
#define IFUNC_ONE_LINE (0<<3)
#define IFUNC_DISPLAY_ON (1<<2)
#define IFUNC_DISPLAY_OFF (0<<2)
#define INSTR_SET_CGRAM_ADDR(x) (0x40|((x)&0x3F)) // 39 uS
#define INSTR_SET_DDRAM_ADDR(x) (0x80|((x)&0x7F)) // 39 uS
#define LUMEX_SO2004DSR_NUM_COLUMNS 20
#define LUMEX_SO2004DSR_NUM_ROWS 4
#define LED_PORT 0
#define LED_PIN 7
#define PCA9555D_I2C_ADDR 0x40>>1 //IICÈ¡7Î»µØÖ·£¬ËùÒÔÐèÒªÓÒÒÆÒ»Î»
#define PROGRAM_KEYPAD_GREEN_LED_ON 0x01 // Exercise 2: actual value to be found
#define PROGRAM_KEYPAD_GREEN_LED_OFF 0x00 // Exercise 2: actual value to be found
UCHAR F4_Flag = 0;
uint32_t LEDOn, LEDOff;
uint32_t uTimeCnt=0;
/* I2C driver instance */
extern ARM_DRIVER_I2C Driver_I2C0;
static ARM_DRIVER_I2C *I2Cdrv = &Driver_I2C0;
struct LPC_PORT
{
uint32_t uPort;
uint32_t uPin;
};
/*********************************************************************************************************
* Keypad_Write()
*
* Description : Function to write to the Keypad Controller (PCA9555)
*
* Argument(s) : Address of the register to be accessed and data to write to that register
*
* Return(s) : none.
*********************************************************************************************************/
void Keypad_Write(UCHAR Reg_Ptr, UCHAR Data_Write)
{
I2C_Data_Write_Buffer[0] = Reg_Ptr;
I2C_Data_Write_Buffer[1] = Data_Write;
I2Cdrv->MasterTransmit (PCA9555D_I2C_ADDR, I2C_Data_Write_Buffer, 2, false);
while (I2Cdrv->GetStatus().busy);
}
/*********************************************************************************************************
* Keypad_Read()
*
* Description : Function to read from the Keypad Controller (PCA9555)
*
* Argument(s) : Address of the register to be accessed and data to be read from that register
*
* Return(s) : none.
*********************************************************************************************************/
UCHAR Keypad_Read(void)
{
I2Cdrv->MasterTransmit (PCA9555D_I2C_ADDR, I2C_Data_Read_Buffer, 1, true);
while (I2Cdrv->GetStatus().busy){;}
I2Cdrv->MasterReceive (PCA9555D_I2C_ADDR, &I2C_Data_Read_Buffer[1], 1, false); //»ñÈ¡µØÖ·ÉÏµÄÊý¾Ý
while (I2Cdrv->GetStatus().busy){;}
//I2C_ReadReg(PCA9555_ADDRESS, I2C_Data_Read_Buffer,1,0);
return I2C_Data_Read_Buffer[1];
}
/*********************************************************************************************************
* Keypad_Init()
*
* Description : Initialize the Keypad Controller (PCA9555)
* Registers to be written:
* 0x02: Program Port 0 (MSB = 0.7 - LSB = 0.0) ; 0: Port = 0 1: Port = 1
* 0x03: Program Port 1 (MSB = 1.7 - LSB = 1.0) ; 0: Port = 0 1: Port = 1
* 0x06: Configure Port 0 (MSB = 0.7 - LSB = 0.0) ; 0: Port = output 1: Port = input
* 0x07: Configure Port 1 (MSB = 1.7 - LSB = 1.0) ; 0: Port = output 1: Port = input
* Argument(s) : none.
*
* Return(s) : none.
*********************************************************************************************************/
void Keypad_Init(void)
{
Keypad_Write(0x06, P0_7_LED_OUT_REG & P0_6_BACKLIGHT_OUT_REG); // Program output port 0 7F&BF 01111111&10111111=00111111 1 is input;
Keypad_Write(0x07, P1_7_6_LED_OUT_REG & P1_KPAD_ROW_OUT_REG); // Program output port 1 3F&C0 00111111&11000000=00000000 all is output
Keypad_Write(0x03,0xC0); // Program Port1 - LEDs off and Kpad Column = 0
}
/*********************************************************************************************************
* Decode_Column()
*
* Description : Decode the column of the pressed key
* Input Register has been read in UCHAR KeypadCheck(void) in app_keyboard.c
*
* Argument(s) : none.
*
* Return(s) : none.
*********************************************************************************************************/
void Decode_Column(void)
{
I2C_Read_Counter+=1;
/* Check value of the PCA9555's Input Register and store Column value accordingly */
switch (Keypad_Data_Read | P1_KPAD_COLUMN_MASK)
{
case 0xFE: Column_Value = 0;
break;
case 0xFD: Column_Value = 1;
break;
case 0xFB: Column_Value = 2;
break;
case 0xF7: Column_Value = 3;
break;
case 0xEF: Column_Value = 4;
break;
case 0xDF: Column_Value = 5;
break;
default: break;
}
}
/*********************************************************************************************************
* Decode_Row()
*
* Description : Decode the row of the pressed key
*
* Argument(s) : none.
*
* Return(s) : none.
**********************************************************************************************/
void Decode_Row(void)
{
UCHAR Keypad_Data_Read;
UCHAR Keypad_Data_Read_Masked;
Row_Counter = 0;
I2C_Write_Counter=0;
I2C_Read_Counter=0;
Row_Found=0;
/*Perform the loop to check ALL the rows (0 to 5) - Write to the Output register accordingly */
do
{
if (Row_Counter == 0)
{
Keypad_Write(0x03,0xFE);
}
if (Row_Counter == 1)
{
Keypad_Write(0x03,0xFC);
}
if (Row_Counter == 2)
{
Keypad_Write(0x03,0xF8);
}
if (Row_Counter == 3)
{
Keypad_Write(0x03,0xF0);
}
if (Row_Counter == 4)
{
Keypad_Write(0x03,0xE0);
}
if (Row_Counter == 5)
{
Keypad_Write(0x03,0xC0);
}
I2C_Write_Counter+=1;
I2C_Data_Read_Buffer[0]=0;
I2C_Data_Read_Buffer[1]=0;
Keypad_Data_Read = Keypad_Read(); // Read Input Register
I2C_Read_Counter+=1;
Keypad_Data_Read_Masked = Keypad_Data_Read | P1_KPAD_COLUMN_MASK;
if (Keypad_Data_Read_Masked != 0xFF) // Check if Read Data is different from 0xFF = Row has been found when no 0xFF
{
if (Row_Found == 0)
{
Row_Value = Row_Counter; // Store Row Value
Row_Found = 1;
}
}
Row_Counter+=1;
} while (Row_Counter <= KPAD_NB_ROW-1);
}
/*********************************************************************************************************
* Keypad_Map()
*
* Description : Map the Row and Column values found in Decode_Row() and Decode_Column() to a specific key
*
* Argument(s) : none.
*
* Return(s) : Pressed Key.
*********************************************************************************************************/
UCHAR Keypad_Map(void)
{
UCHAR lKey = 0;
if (Column_Value == 5)
{
if (Row_Value == 0) lKey = KEY_F4;
else if (Row_Value == 1) lKey = KEY_ARW_UP;
else if (Row_Value == 2) lKey = KEY_PLUS;
else if (Row_Value == 3) lKey = KEY_F3;
else if (Row_Value == 4) lKey = KEY_F2;
else if (Row_Value == 5) lKey = KEY_F1;
}
else if (Column_Value == 4)
{
if (Row_Value == 0) lKey = KEY_MENU;
else if (Row_Value == 1) lKey = KEY_ARW_DN;
else if (Row_Value == 2) lKey = KEY_MINUS;
else if (Row_Value == 3) lKey = KEY_ARW_RT;
else if (Row_Value == 4) lKey = KEY_OK;
else if (Row_Value == 5) lKey = KEY_ARW_LT;
}
else if (Column_Value == 3)
{
if (Row_Value == 0) lKey = KEY_ERROR;
else if (Row_Value == 1) lKey = KEY_3;
else if (Row_Value == 2) lKey = KEY_2;
else if (Row_Value == 3) lKey = KEY_1;
else if (Row_Value == 4) lKey = KEY_CLEAR;
else if (Row_Value == 5) lKey = KEY_SEND;
}
else if (Column_Value == 2)
{
if (Row_Value == 0) lKey = KEY_ERROR;
else if (Row_Value == 1) lKey = KEY_ERROR;
else if (Row_Value == 2) lKey = KEY_7;
else if (Row_Value == 3) lKey = KEY_6;
else if (Row_Value == 4) lKey = KEY_5;
else if (Row_Value == 5) lKey = KEY_4;
}
else if (Column_Value == 1)
{
if (Row_Value == 0) lKey = KEY_ERROR;
else if (Row_Value == 1) lKey = KEY_POUND;
else if (Row_Value == 2) lKey = KEY_0;
else if (Row_Value == 3) lKey = KEY_ASTERISK;
else if (Row_Value == 4) lKey = KEY_9;
else if (Row_Value == 5) lKey = KEY_8;
}
else if (Column_Value == 0)
{
lKey = KEY_END;
}
return lKey;
}
/*********************************************************************************************************
* Keypad_Decoder()
*
* Description : Keypad_Decoder Function
* 1) Decode the column
* 2) Decode the row
* 3) Map the coordinate to a key
*
* Argument(s) : none.
*
* Return(s) : Pressed Key.
*********************************************************************************************************/
UCHAR Keypad_Decoder (void)
{
Decode_Column();
Decode_Row();
return Keypad_Map();
}
/*----------------------------------------------------------------------------
SysTick IRQ Handler
*----------------------------------------------------------------------------*/
void SysTick_Handler (void)
{
uTimeCnt++;
}
/* Initialize I2C connected SA56004 */
int32_t PCA9555D_Initialize (void)
{
I2Cdrv->Initialize (NULL);
I2Cdrv->PowerControl (ARM_POWER_FULL);
I2Cdrv->Control (ARM_I2C_BUS_SPEED, ARM_I2C_BUS_SPEED_STANDARD);
I2Cdrv->Control (ARM_I2C_BUS_CLEAR, 0);
return 1;
}
int32_t Delayms(uint32_t ms)
{
uTimeCnt=0;
while(uTimeCnt<ms){};
return 0;
}
int32_t LED_Initialize (void)
{
/* Enable GPIO clock */
GPIO_PortClock (1);
/* Configure pins: Output Mode with Pull-down resistors */
PIN_Configure (LED_PORT, LED_PIN, PIN_FUNC_0, PIN_PINMODE_PULLDOWN, PIN_PINMODE_NORMAL);
GPIO_SetDir (LED_PORT, LED_PIN, GPIO_DIR_OUTPUT);
GPIO_PinWrite (LED_PORT, LED_PIN, 0);
return 0;
}

复制代码

主函数如下：

/*----------------------------------------------------------------------------
Main function
*----------------------------------------------------------------------------*/
int main (void)
{
char buff[40];
uint8_t uLedState=0;
UCHAR keypadval=0;
SystemCoreClockUpdate (); /* Update system core clock */
SysTick_Config(SystemCoreClock/1000); /* Generate interrupt each 1 ms */
LED_Initialize(); /* LED Initialization */
PCA9555D_Initialize();
Keypad_Init();
LCD_Init();
LCD_WR_Str("Welcome used LPC1768");
while (1)
{
I2C_Data_Read_Buffer[0]=0;
I2C_Data_Read_Buffer[1]=0;
Keypad_Data_Read=Keypad_Read();
if((Keypad_Data_Read|P1_KPAD_COLUMN_MASK)!=0xFF)
{
keypadval=Keypad_Decoder();
sprintf(buff,"CurKeypad value:%d",keypadval);
LCD_Set_RowCol(0,2);
LCD_WR_Str(buff);
}else
{
memset(buff,0,sizeof(buff));
sprintf(buff,"No Key Pressed! ");
LCD_Set_RowCol(0,2);
LCD_WR_Str(buff);
}
GPIO_PinWrite(LED_PORT, LED_PIN, uLedState); /* Turn specified LED off */
uLedState=!uLedState;
Delayms(100);
}
}

复制代码

本次实现按下键时获取对应键值的结果如下所示：
演示效果.gif

阅读全文

8zhangben · 发表于 2019-4-30 10:31:20

谢谢分享

[原创] 【LPC1768-DEV】⑤读按键值

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