MSP430F6638按下key1控制led灯的亮灭并记录按键次数显示在lcd屏上，按照key2用flash存储当前的按键次数，断电再开机，再次按下key2在lcd上显示断电前保存的次数

好的，这是一个比较典型的嵌入式系统应用，需要结合MSP430F6638的GPIO、LCD和Flash模块进行编程实现。下面是一个大致的代码框架：

#include <msp430.h>
#include <stdint.h>

#define KEY1 BIT0
#define KEY2 BIT1
#define LED BIT2
#define LCD_RS BIT3
#define LCD_E BIT4
#define LCD_DB4 BIT5
#define LCD_DB5 BIT6
#define LCD_DB6 BIT7
#define LCD_DB7 BIT8

#define CMD_CLEAR_LCD 0x01
#define CMD_RETURN_HOME 0x02
#define CMD_ENTRY_MODE_SET 0x04
#define CMD_DISPLAY_CONTROL 0x08
#define CMD_FUNCTION_SET 0x20
#define CMD_SET_CGRAM_ADDR 0x40
#define CMD_SET_DDRAM_ADDR 0x80

#define ENTRY_MODE_INCREMENT 0x02
#define ENTRY_MODE_SHIFT_CURSOR 0x00
#define DISPLAY_CONTROL_DISPLAY_ON 0x04
#define DISPLAY_CONTROL_CURSOR_ON 0x02
#define DISPLAY_CONTROL_BLINK_ON 0x01
#define FUNCTION_SET_8BIT_MODE 0x10
#define FUNCTION_SET_2LINE_MODE 0x08
#define FUNCTION_SET_FONT_5X8 0x00

#define FLASH_START_ADDR 0x1800

void lcd_write_nibble(uint8_t nibble, uint8_t rs);
void lcd_write_byte(uint8_t byte, uint8_t rs);
void lcd_init();
void lcd_clear();
void lcd_return_home();
void lcd_set_cursor(uint8_t row, uint8_t col);
void lcd_write_char(char c);
void lcd_write_string(const char* str);
void delay_ms(unsigned int ms);
void flash_write(uint16_t addr, uint8_t data);
uint8_t flash_read(uint16_t addr);

volatile uint8_t key1_pressed = 0;
volatile uint8_t key2_pressed = 0;
volatile uint8_t key2_released = 0;
volatile uint16_t key1_count = 0;
volatile uint16_t key2_count = 0;

int main(void) {
    WDTCTL = WDTPW | WDTHOLD;   // stop watchdog timer
    PM5CTL0 &= ~LOCKLPM5;       // disable high-impedance mode
    P1DIR |= LED;               // set LED pin as output
    P1OUT &= ~LED;              // turn off LED
    P1REN |= KEY1 | KEY2;       // enable pull-up resistors on key pins
    P1IE |= KEY1 | KEY2;        // enable interrupts on key pins
    P1IES |= KEY1 | KEY2;       // trigger interrupt on falling edge
    P1IFG &= ~(KEY1 | KEY2);    // clear interrupt flags on key pins
    lcd_init();                 // initialize LCD
    lcd_clear();                // clear LCD screen
    delay_ms(10);               // wait for LCD to stabilize
    lcd_write_string("Press Key1."); // display initial message
    __enable_interrupt();       // enable global interrupts
    while (1) {
        if (key1_pressed) {     // handle Key1 press
            key1_pressed = 0;
            P1OUT ^= LED;       // toggle LED
            key1_count++;       // increment count
            lcd_set_cursor(1, 0); // set cursor to second line
            lcd_write_string("Key1: ");
            lcd_write_char(key1_count / 100 + '0'); // display count
            lcd_write_char((key1_count / 10) % 10 + '0');
            lcd_write_char(key1_count % 10 + '0');
        }
        if (key2_pressed) {     // handle Key2 press
            key2_pressed = 0;
            key2_count = key1_count; // save count to flash
            flash_write(FLASH_START_ADDR, key2_count >> 8);
            flash_write(FLASH_START_ADDR + 1, key2_count & 0xFF);
            lcd_set_cursor(1, 0); // set cursor to second line
            lcd_write_string("Key2: Saved.");
            delay_ms(500);
            lcd_clear();        // clear LCD screen
            lcd_write_string("Press Key1."); // display initial message
        }
        if (key2_released) {    // handle Key2 release
            key2_released = 0;
            uint16_t saved_count = (flash_read(FLASH_START_ADDR) << 8)
                | flash_read(FLASH_START_ADDR + 1); // read count from flash
            lcd_set_cursor(1, 0); // set cursor to second line
            lcd_write_string("Key2: ");
            lcd_write_char(saved_count / 100 + '0'); // display count
            lcd_write_char((saved_count / 10) % 10 + '0');
            lcd_write_char(saved_count % 10 + '0');
        }
    }
}

#pragma vector=PORT1_VECTOR
__interrupt void PORT1_ISR() {
    if (P1IFG & KEY1) {         // handle Key1 interrupt
        key1_pressed = 1;
        P1IFG &= ~KEY1;         // clear interrupt flag
    }
    if (P1IFG & KEY2) {         // handle Key2 interrupt
        if (P1IN & KEY2) {      // handle Key2 release
            key2_released = 1;
        } else {                // handle Key2 press
            key2_pressed = 1;
        }
        P1IFG &= ~KEY2;         // clear interrupt flag
    }
}

void lcd_write_nibble(uint8_t nibble, uint8_t rs) {
    if (rs) {
        P1OUT |= LCD_RS;
    } else {
        P1OUT &= ~LCD_RS;
    }
    P1OUT &= ~(LCD_DB4 | LCD_DB5 | LCD_DB6 | LCD_DB7);
    P1OUT |= (nibble << 4) & (LCD_DB4 | LCD_DB5 | LCD_DB6 | LCD_DB7);
    P1OUT |= LCD_E;
    delay_ms(1);
    P1OUT &= ~LCD_E;
    delay_ms(1);
}

void lcd_write_byte(uint8_t byte, uint8_t rs) {
    lcd_write_nibble(byte >> 4, rs);
    lcd_write_nibble(byte & 0x0F, rs);
}

void lcd_init() {
    P1DIR |= LCD_RS | LCD_E | LCD_DB4 | LCD_DB5 | LCD_DB6 | LCD_DB7;
    delay_ms(50);
    lcd_write_nibble(0x03, 0);
    delay_ms(5);
    lcd_write_nibble(0x03, 0);
    delay_us(100);
    lcd_write_nibble(0x03, 0);
    delay_us(100);
    lcd_write_nibble(0x02, 0);
    lcd_write_byte(CMD_FUNCTION_SET | FUNCTION_SET_8BIT_MODE, 0);
    lcd_write_byte(CMD_DISPLAY_CONTROL | DISPLAY_CONTROL_DISPLAY_ON, 0);
    lcd_write_byte(CMD_ENTRY_MODE_SET | ENTRY_MODE_INCREMENT, 0);
    lcd_write_byte(CMD_CLEAR_LCD, 0);
}

void lcd_clear() {
    lcd_write_byte(CMD_CLEAR_LCD, 0);
    delay_ms(2);
}

void lcd_return_home() {
    lcd_write_byte(CMD_RETURN_HOME, 0);
    delay_ms(2);
}

void lcd_set_cursor(uint8_t row, uint8_t col) {
    uint8_t addr = col;
    if (row == 1) {
        addr += 0x40;
    }
    lcd_write_byte(CMD_SET_DDRAM_ADDR | addr, 0);
}

void lcd_write_char(char c) {
    lcd_write_byte(c, 1);
}

void lcd_write_string(const char* str) {
    while (*str) {
        lcd_write_char(*str++);
    }
}

void delay_ms(unsigned int ms) {
    __delay_cycles(1000 * ms);
}

void flash_write(uint16_t addr, uint8_t data) {
    FCTL3 = FWKEY;              // unlock flash
    FCTL1 = FWKEY | WRT;        // enable write mode
    *((uint8_t*)addr) = data;   // write byte to flash
    FCTL1 = FWKEY;              // disable write mode
    FCTL3 = FWKEY | LOCK;       // lock flash
}

uint8_t flash_read(uint16_t addr) {
    return *((uint8_t*)addr);   // read byte from flash
}

在这个代码框架中，我们首先定义了一些常量，例如按键、LED、LCD和Flash的引脚和指令，以及保存计数值的Flash地址。然后定义了一些函数，如LCD的基本操作函数、延时函数和Flash的读写函数。在`main()`函数中初始化各个模块，并进入主循环。主循环中，通过轮询的方式检查是否有按键按下或释放，并根据按键采取相应的操作。具体来说：

- 当检测到Key1按下时，翻转LED并增加计数值，然后在LCD上显示计数值。
- 当检测到Key2按下时，将当前计数值保存到Flash中，并在LCD上显示“Saved.”的提示信息。
- 当检测到Key2释放时，从Flash中读取之前保存的计数值，并在LCD上显示该值。

在中断服务函数中，我们通过检查P1IFG寄存器来确定是哪个按键触发了中断，然后设置相应的标志位，在主循环中处理。

需要注意的是，LCD的初始化过程较为复杂，需要通过发送一系列指令来设置其工作模式和显示内容。在实际应用中，可能需要根据具体的LCD型号和接口来进行相应的修改。同时，Flash的写操作可能需要进行一些额外的保护，例如在写之前先擦除整个Flash扇区。