基于MSP430简易示波器的设计

1、基于MSP430简易示波器的设计自动化1107王诗雨2013.121. 硬件设计1.1 单片机选用MSP430G2553单片机，该单片机具有低功耗的特点，内部自带8路10位AD转换器（ADC10），最高主频可达16Mhz，对于一个简易示波器来说这些特点足够我们使用。1.2 程控放大电路程控放大电路的作用是对大信号进行衰减，对小信号进行放大，保证输入到AD转换器的信号幅度在要求的输入电压范围内，以达到最好的测量与观察效果。采用模拟开关CD4051，配合精密电位器实现多挡垂直分辨率。在MSP430单片机中使用寄存器模块设置通道号，通过写入通道号控制模拟开关选通不同的反馈电阻，从而实现不同的放大倍数

2、，对信号进行不同程度的放大（衰减）。电路图如下:1.3 简易调理电路由于示波器观察信号大多是正负电压信号，考虑到ADC10一般使用的是单极性参考电压（也可以使用寄存器设置双极性参考电压，这样就不需要调理电路了，但最好加一级缓冲）。为了采样到信号的负电压，就需要给该信号叠加直流量，将负电压部分信号抬高至零电平以上，因此采用信号调理电路。电路图如下：1.4 LCD显示电路和按键电路利用LCD的SPI通信模式与MSP430单片机连接，这样可以得到不错的通信速度，并且可以尽可能的减少MSP430引脚的占用，具体电路这里就不给出了。（按照spi连接）利用简单独立按键实现放大倍数调节，采样频率设置等功能即

3、可。2.软件设计2.1 单片机初始化对P2口初始化，打开P2口的中断；将通信方式设置为硬件spi通信模式（注意spi通信在上升沿还是在下降沿开始）。WDTCTL=WDTPW+WDTHOLD; /关看门狗P1OUT = 0x00; / P1 setup for LED & reset output P1DIR |= BIT0 + BIT2 + BIT3 + BIT4 + BIT5; P1SEL = BIT1 + BIT2 + BIT4; P1SEL2 = BIT1 + BIT2 + BIT4; P2REN |= 0x38; P2DIR = 0x07; P2OUT = 0; P2IE |=

4、 0x38; / P1.4 interrupt enabled P2IFG &= 0x38; will=0; UCA0CTL0 |= UCCKPL + UCMSB + UCMST + UCSYNC + UCCKPH ; / 3-pin, 8-bit SPI master UCA0CTL1 |= UCSSEL_2; / SMCLK UCA0BR0 |= 0x04; / /2 UCA0BR1 = 0; / UCA0MCTL = 0; / No modulation UCA0CTL1 &= UCSWRST; / *Initialize USCI state machine* P1OU

5、T &= BIT5; / Now with SPI signals initialized, P1OUT |= BIT5; / reset slaveADC10初始化，开启参考源和中断。ADC10CTL0 = ADC10SHT_0 + REFON + ADC10ON + ADC10IE;ADC10CTL1 = INCH_6;ADC10AE0 |= 0x40; 显示初始化，对LCD的界面显示初始化。Initial_ILI9340C();Delay_ms(300);LCD_TEST_SingleColor(Black);LCD_TEST_SingleColor(Black);LCD_TES

6、T_PartColor(Blue);for(wh=22; wh<220 ;wh+=10)LCD_draw_Line(wh,39,White);LCD_draw_Line(wh,79,White);LCD_draw_Line(wh,119,White);LCD_draw_Line(wh,159,White);LCD_draw_Line(wh,199,White);LCD_draw_Line(wh,239,White);LCD_draw_Line(wh,279,White);Delay_ms(100);for(co=2; co<320 ;co+=10)LCD_draw_Col(69,c

7、o,White);LCD_draw_Col(119,co,White);LCD_draw_Col(169,co,White);Delay_ms(100);2.2 程控选择程序根据按键的次数，在P2口中断改变will的值，并通过P2口输出给CD4051的ABC开关选择端，对放大倍数进行选择。 #pragma vector=PORT2_VECTOR_interrupt void Port_2(void)if(P2IFG & 0x10)while(0x10 & P2IN);will+;if(will=8)will=7;if(P2IFG & 0x20)while(0x20 &a

8、mp; P2IN);will-;if(will=255)will=0;if(P2IFG & 0x08)while(0x08 & P2IN);chan+;if(chan=4)chan=0; P2IFG &= 0x38; P2OUT=will;2.3 采样频率设置通过改变ADC10CTL1，通过按键次数对应值不同改变ADC10时钟的频率来调节电路的采样频率。 switch(chan) case 0: ADC10CTL1 = INCH_6; break;case 1: ADC10CTL1 |= ADC10DIV0 + ADC10DIV1; break;case 2: ADC1

9、0CTL1 |= ADC10DIV0 + ADC10DIV2; break;case 3: ADC10CTL1 |= ADC10DIV0 + ADC10DIV1 + ADC10DIV2; break;2.4 软件触发程序只有在一定条件下才使lcd刷新，保证每次采集到的波形都从一点开始显示，防止由于每次采集到的点不同导致波形一直移动。ADC10CTL0 |= ENC + ADC10SC; / Sampling and conversion start _bis_SR_register(CPUOFF + GIE); if(cir=0) key1 = ADC10MEM/5; if(cir=1) ke

10、y2 = ADC10MEM/5; if(cir=2) key3 = ADC10MEM/5;if(cir>2 && key1>key2 && key2>key3) /(key1-100)/2)>=(key2-100) temp0=key1; temp1=key2; temp2=key3; tempcir=ADC10MEM/5; ADC10CTL0 &= ENC;2.5 显示刷新程序示波器是一个动态显示过程，因此在过程中可能会引起初始界面被部分覆盖，以此需要定时刷新初始界面。trig+;if(trig%20=0)for(wh=22;

11、wh<220 ;wh+=10)LCD_draw_Line(wh,39,White);LCD_draw_Line(wh,79,White);LCD_draw_Line(wh,119,White);LCD_draw_Line(wh,159,White);LCD_draw_Line(wh,199,White);LCD_draw_Line(wh,239,White);LCD_draw_Line(wh,279,White);Delay_ms(300);for(co=2; co<320 ;co+=10)LCD_draw_Col(69,co,White);LCD_draw_Col(119,co,

12、White);LCD_draw_Col(169,co,White);Delay_ms(300);附：源程序#include "msp430g2553.h" /STC12单片机头文件/颜色定义#define Blue 0x001f#define Yellow0xffe0#define Green 0x07e0#define Black0x0000#define White0xffff#define Red0xf800/引脚定义#defineR_ESET1 P1OUT|=BIT5; /液晶RESET引脚,接单片机IO引脚#define R_ESET0 P1OUT&=BI

13、T5;#defineC_D1P1OUT|=BIT3;/液晶D/CX引脚，数据/命令控制，接单片机IO引脚#defineC_D0 P1OUT&=BIT3;#defineC_S1 P1OUT|=BIT0;/液晶片选CS,P1.4为单片机SPI总线的SS引脚,通过MSTR位配置为IO模式#defineC_S0 P1OUT&=BIT0;unsigned char MST_Data, SLV_Data, wh, temp320, trig=0, key1, key2 ,key3 ,will ,chan=0;unsigned int co,cir;void delay(void) unsi

14、gned int j; for(j=100;j>0;j-);void Delay_us(int value)/延时函数_uswhile (value)value-;void Delay_ms(int value)/延时函数_mswhile (value)Delay_us(999);value-;void LCD_Writ_Bus(char a) /数据写入函数 8位 C_S0; UCA0TXBUF = a; _delay_cycles(50); while (!(IFG2 & UCA0TXIFG); C_S1;void LCD_WRITE_CMD(char cmd)/8 bit

15、C_D0; LCD_Writ_Bus(cmd);void LCD_WRITE_COM_DATA(char com_data)/8 bit C_D1; LCD_Writ_Bus(com_data);void LCD_WRITE_DATA(int a)/16位数据,分两次，每次送8位 C_D1; LCD_Writ_Bus(a>>8); LCD_Writ_Bus(a);/设置绘点窗口，x=0239,y=0319void Address_set(unsigned int x1,unsigned int x2,unsigned int y1,unsigned int y2) LCD_WRIT

16、E_CMD(0x2a); /x轴 LCD_WRITE_DATA(x1); LCD_WRITE_DATA(x2); LCD_WRITE_CMD(0x2b); /y轴 LCD_WRITE_DATA(y1); LCD_WRITE_DATA(y2); LCD_WRITE_CMD(0x2c);void LCD_TEST_SingleColor(int Discolor) int i,j;Address_set(0,239,0,319);for (i=0;i<320;i+)for (j=0;j<240;j+)LCD_WRITE_DATA(Discolor);void LCD_TEST_Part

17、Color(int Discolor) int i,j;Address_set(0,19,0,319);for (i=0;i<320;i+)for (j=0;j<20;j+)LCD_WRITE_DATA(Discolor);Address_set(220,239,0,319);for (i=0;i<320;i+)for (j=220;j<240;j+)LCD_WRITE_DATA(Discolor);/画一条横线void LCD_draw_Line(unsigned int x,unsigned int y,unsigned int color)int i;Addres

18、s_set(x,x+4,y,y);for (i=0;i<5;i+)LCD_WRITE_DATA(color);void LCD_draw_Col(unsigned int x,unsigned int y,unsigned int color)int i;Address_set(x,x,y,y+4);for (i=0;i<5;i+)LCD_WRITE_DATA(color);/液晶主控初始化void Initial_ILI9340C(void) LCD_WRITE_CMD(0xCB); LCD_WRITE_COM_DATA(0x39); LCD_WRITE_COM_DATA(0x2

19、C); LCD_WRITE_COM_DATA(0x00); LCD_WRITE_COM_DATA(0x34); LCD_WRITE_COM_DATA(0x02); LCD_WRITE_CMD(0xCF); LCD_WRITE_COM_DATA(0x00); LCD_WRITE_COM_DATA(0XC1); LCD_WRITE_COM_DATA(0X30); LCD_WRITE_CMD(0xE8); LCD_WRITE_COM_DATA(0x85); LCD_WRITE_COM_DATA(0x00); LCD_WRITE_COM_DATA(0x78); LCD_WRITE_CMD(0xEA);

20、 LCD_WRITE_COM_DATA(0x00); LCD_WRITE_COM_DATA(0x00); LCD_WRITE_CMD(0xED); LCD_WRITE_COM_DATA(0x64); LCD_WRITE_COM_DATA(0x03); LCD_WRITE_COM_DATA(0X12); LCD_WRITE_COM_DATA(0X81); LCD_WRITE_CMD(0xF7); LCD_WRITE_COM_DATA(0x20); LCD_WRITE_CMD(0xC0); /Power control LCD_WRITE_COM_DATA(0x23); /VRH5:0 LCD_W

21、RITE_CMD(0xC1); /Power control LCD_WRITE_COM_DATA(0x10); /SAP2:0;BT3:0 LCD_WRITE_CMD(0xC5); /VCM control LCD_WRITE_COM_DATA(0x3e); /对比度调节 LCD_WRITE_COM_DATA(0x28); LCD_WRITE_CMD(0xC7); /VCM control2 LCD_WRITE_COM_DATA(0x86); /- LCD_WRITE_CMD(0x36); / Memory Access Control LCD_WRITE_COM_DATA(0xC8); L

22、CD_WRITE_CMD(0x3A); LCD_WRITE_COM_DATA(0x55); LCD_WRITE_CMD(0xB1); LCD_WRITE_COM_DATA(0x00); LCD_WRITE_COM_DATA(0x18); LCD_WRITE_CMD(0xB6); / Display Function Control LCD_WRITE_COM_DATA(0x08); LCD_WRITE_COM_DATA(0x82); LCD_WRITE_COM_DATA(0x27); LCD_WRITE_CMD(0xF2); / 3Gamma Function Disable LCD_WRIT

23、E_COM_DATA(0x00); LCD_WRITE_CMD(0x26); /Gamma curve selected LCD_WRITE_COM_DATA(0x01); LCD_WRITE_CMD(0xE0); /Set Gamma LCD_WRITE_COM_DATA(0x0F); LCD_WRITE_COM_DATA(0x31); LCD_WRITE_COM_DATA(0x2B); LCD_WRITE_COM_DATA(0x0C); LCD_WRITE_COM_DATA(0x0E); LCD_WRITE_COM_DATA(0x08); LCD_WRITE_COM_DATA(0x4E);

24、 LCD_WRITE_COM_DATA(0xF1); LCD_WRITE_COM_DATA(0x37); LCD_WRITE_COM_DATA(0x07); LCD_WRITE_COM_DATA(0x10); LCD_WRITE_COM_DATA(0x03); LCD_WRITE_COM_DATA(0x0E); LCD_WRITE_COM_DATA(0x09); LCD_WRITE_COM_DATA(0x00); LCD_WRITE_CMD(0XE1); /Set Gamma LCD_WRITE_COM_DATA(0x00); LCD_WRITE_COM_DATA(0x0E); LCD_WRI

25、TE_COM_DATA(0x14); LCD_WRITE_COM_DATA(0x03); LCD_WRITE_COM_DATA(0x11); LCD_WRITE_COM_DATA(0x07); LCD_WRITE_COM_DATA(0x31); LCD_WRITE_COM_DATA(0xC1); LCD_WRITE_COM_DATA(0x48); LCD_WRITE_COM_DATA(0x08); LCD_WRITE_COM_DATA(0x0F); LCD_WRITE_COM_DATA(0x0C); LCD_WRITE_COM_DATA(0x31); LCD_WRITE_COM_DATA(0x

26、36); LCD_WRITE_COM_DATA(0x0F); LCD_WRITE_CMD(0x11); /Exit Sleep Delay_ms(120); LCD_WRITE_CMD(0x29); /Display on LCD_WRITE_CMD(0x2c);/LCD进入休眠状态void LCD_Sleep_ILI9340C(void) LCD_WRITE_CMD(0x28);/Display off Delay_ms(20); LCD_WRITE_CMD(0x10);/Enter Sleep mode/LCD退出休眠状态void LCD_ExitSleep_ILI9340C(void)

27、LCD_WRITE_CMD(0x11);/Exit Sleep Delay_ms(120); LCD_WRITE_CMD(0x29);/Display on LCD_WRITE_CMD(0x2c);void main()WDTCTL=WDTPW+WDTHOLD; /关看门狗P1OUT = 0x00; / P1 setup for LED & reset output P1DIR |= BIT0 + BIT2 + BIT3 + BIT4 + BIT5; P1SEL = BIT1 + BIT2 + BIT4; P1SEL2 = BIT1 + BIT2 + BIT4; P2REN |= 0x

28、38; P2DIR = 0x07; P2OUT = 0; P2IE |= 0x38; / P1.4 interrupt enabled P2IFG &= 0x38; will=0; UCA0CTL0 |= UCCKPL + UCMSB + UCMST + UCSYNC + UCCKPH ; / 3-pin, 8-bit SPI master UCA0CTL1 |= UCSSEL_2; / SMCLK UCA0BR0 |= 0x04; / /2 UCA0BR1 = 0; / UCA0MCTL = 0; / No modulation UCA0CTL1 &= UCSWRST; /

29、*Initialize USCI state machine* P1OUT &= BIT5; / Now with SPI signals initialized, P1OUT |= BIT5; / reset slave _delay_cycles(75); / Wait for slave to initializeInitial_ILI9340C();Delay_ms(300);LCD_TEST_SingleColor(Black);LCD_TEST_SingleColor(Black);LCD_TEST_PartColor(Blue);for(wh=22; wh<220

30、;wh+=10)LCD_draw_Line(wh,39,White);LCD_draw_Line(wh,79,White);LCD_draw_Line(wh,119,White);LCD_draw_Line(wh,159,White);LCD_draw_Line(wh,199,White);LCD_draw_Line(wh,239,White);LCD_draw_Line(wh,279,White);Delay_ms(100);for(co=2; co<320 ;co+=10)LCD_draw_Col(69,co,White);LCD_draw_Col(119,co,White);LCD

31、_draw_Col(169,co,White);Delay_ms(100);ADC10CTL0 = ADC10SHT_0 + REFON + ADC10ON + ADC10IE; ADC10CTL1 = INCH_6; ADC10AE0 |= 0x40; / PA.1 ADC option selectwhile(1)for(cir=0;cir<320;cir+) ADC10CTL0 |= ENC + ADC10SC; / Sampling and conversion start _bis_SR_register(CPUOFF + GIE); / LPM0, ADC10_ISR wil

32、l force exi if(cir=0) key1 = ADC10MEM/5; if(cir=1) key2 = ADC10MEM/5; if(cir=2) key3 = ADC10MEM/5; if(cir>2 && key1>key2 && key2>key3) /(key1-100)/2)>=(key2-100) temp0=key1; temp1=key2; temp2=key3; tempcir=ADC10MEM/5; ADC10CTL0 &= ENC; switch(chan)case 0: ADC10CTL1 =

33、INCH_6; break;case 1: ADC10CTL1 |= ADC10DIV0 + ADC10DIV1; break;case 2: ADC10CTL1 |= ADC10DIV0 + ADC10DIV2; break;case 3: ADC10CTL1 |= ADC10DIV0 + ADC10DIV1 + ADC10DIV2; break;for(cir=0;cir<320;cir+)Address_set(20+tempcir,20+tempcir,cir,cir);LCD_WRITE_DATA(Yellow);Delay_ms(300);for(cir=0;cir<320;cir+)Address_set(20+tempcir,20+tempcir,cir,cir);LCD_WRITE_DATA(Yellow);Delay_ms(300);for(cir=0;c