1、/*/*大氣壓檢測GY68 BMP180 模塊編譯器編寫手頭上有塊BMP180氣壓傳感模塊，為了好玩，想用之作一車載氣壓表。在網上找AVR驅動未果，就用來自網絡BMP085模塊C51單片機IIC測試程序修改，測試成功，方便初學AVR的參考；聽說BMP180航模上也可以用。效果圖：模塊：GY68 BMP180 編譯器：winavr V2.0.8單片機：MEGA16作者：十堰供電 DXY*/* #include <avr/io.h> #include <util/delay.h>#include <math.h>#define SDA68_L PORTB &am

2、p;= (1<<PB0) #define SDA68_H PORTB |= (1<<PB0)#define SCL68_L PORTB &= (1<<PB1) #define SCL68_H PORTB |= (1<<PB1)#define SDA68_DDR_0 DDRB &= (1<<PB0)#define SDA68_DDR_1 DDRB |= (1<<PB0) #define SCL68_DDR_0 DDRB &= (1<<PB1)#define SCL68_DDR_1 DDRB

3、 |= (1<<PB1)#define SDA68_RD_VAL(PINB & _BV(PB0)#define BMP085_SlaveAddress 0xee /定義器件在IIC總線中的從地址 #define OSS 0 / Oversampling Setting (note: code is not set up to use other OSS values)#define uchar unsigned char int dis_data; /變量short ac1;short ac2; short ac3; unsigned short ac4;unsigned

4、short ac5;unsigned short ac6;short b1; short b2;short mb;short mc;short md;uchar HorL;uchar ge,shi,bai,qian,wan,shiwan;/*起始信號*/void BMP085_Start(void) SDA68_H; /拉高數據線 SCL68_H;SDA68_DDR_1;SCL68_DDR_1; /拉高時鐘線 _delay_us(5); /延時 SDA68_L; /產生下降沿 _delay_us(5); /延時 SCL68_L; /拉低時鐘線SDA68_DDR_1;/拉高，置為輸出SCL68_

5、DDR_1;/*停止信號*/void BMP085_Stop(void) SDA68_L; /拉低數據線 SCL68_H; SDA68_DDR_1;SCL68_DDR_1; /拉高時鐘線 _delay_us(5); /延時 SDA68_H; /產生上升沿 _delay_us(5); /延時SDA68_DDR_1;/拉高，置為輸出SCL68_DDR_1;/*發送應答信號入口參數:ack (0:ACK 1:NAK)*/void BMP085_SendACK(uchar ack)SDA68_DDR_1;/拉高，置為輸出SCL68_DDR_1;if (ack) SDA68_H;/寫應答else SDA

6、68_L; SCL68_H; /拉高時鐘線 _delay_us(5); /延時 SCL68_L; /拉低時鐘線 _delay_us(5); /延時SDA68_DDR_1;/拉高，置為輸出SCL68_DDR_1;/*接收應答信號*/uchar BMP085_RecvACK(void) SCL68_H; /拉高時鐘線 SDA68_DDR_0;/拉低，置為輸入SCL68_DDR_1;_delay_us(5); /延時 if (SDA68_RD_VAL) HorL =1;else HorL =0; SCL68_L; /拉低時鐘線 _delay_us(5); /延時SDA68_DDR_1;/拉高，置為輸

7、出SCL68_DDR_1;return HorL;/*向IIC總線發送一個字節數據*/void BMP085_SendByte(char dat) SDA68_DDR_1;/DDRA |=_BV(PA0);SCL68_DDR_1;uchar i; for (i=0; i<8; i+) /8位計數器 /dat <<= 1; /移出數據的最高位 /SDA68 = CY; /送數據口 if (dat&0x80) SDA68_H;else SDA68_L;dat <<= 1;SCL68_H; /拉高時鐘線 _delay_us(5); /延時 SCL68_L; /拉

8、低時鐘線 _delay_us(5); /延時 SDA68_DDR_1;/拉高，置為輸出SCL68_DDR_1; BMP085_RecvACK();/*從IIC總線接收一個字節數據*/uchar BMP085_RecvByte(void) uchar i,dat = 0; SDA68_H;SDA68_DDR_1; /使能內部上拉,準備讀取數據,for (i=0; i<8; i+) /8位計數器 dat<<=1;SCL68_H;SCL68_DDR_0;_delay_us(5);dat |= SDA68_RD_VAL;SCL68_L;SCL68_DDR_1;_delay_us(5)

9、;return dat;/*/讀出BMP085內部數據,連續兩個/*short Multiple_read(uchar ST_Address) uchar msb, lsb; short _data; BMP085_Start(); /起始信號 BMP085_SendByte(BMP085_SlaveAddress); /發送設備地址+寫信號 BMP085_SendByte(ST_Address); /發送存儲單元地址 BMP085_Start(); /起始信號 BMP085_SendByte(BMP085_SlaveAddress+1); /發送設備地址+讀信號 msb = BMP085_R

10、ecvByte(); /BUF0存儲 BMP085_SendACK(0); /回應ACK lsb = BMP085_RecvByte(); BMP085_SendACK(1); /最后一個數據需要回NOACK BMP085_Stop(); /停止信號 _delay_ms(5); _data = msb << 8; _data |= lsb; return _data;/*long bmp085ReadTemp(void) BMP085_Start(); /起始信號 BMP085_SendByte(BMP085_SlaveAddress); /發送設備地址+寫信號 BMP085_Se

11、ndByte(0xF4); / write register address BMP085_SendByte(0x2E); / write register data for temp BMP085_Stop(); /發送停止信號 _delay_ms(10); / max time is 4.5ms return (long) Multiple_read(0xF6);/*long bmp085ReadPressure(void) long pressure = 0; BMP085_Start(); /起始信號 BMP085_SendByte(BMP085_SlaveAddress); /發送設

12、備地址+寫信號 BMP085_SendByte(0xF4); / write register address BMP085_SendByte(0x34); / write register data for pressure BMP085_Stop(); /發送停止信號 _delay_ms(10); / max time is 4.5ms pressure = Multiple_read(0xF6); pressure &= 0x0000FFFF; return pressure; /return (long) bmp085ReadShort(0xF6);/*/初始化BMP085，根

13、據需要請參考pdf進行修改*void Init_BMP085(void) ac1 = Multiple_read(0xAA); ac2 = Multiple_read(0xAC); ac3 = Multiple_read(0xAE); ac4 = Multiple_read(0xB0); ac5 = Multiple_read(0xB2); ac6 = Multiple_read(0xB4); b1 = Multiple_read(0xB6); b2 = Multiple_read(0xB8); mb = Multiple_read(0xBA); mc = Multiple_read(0xBC

14、); md = Multiple_read(0xBE);/讀數分解void conver085(long temp_data) /long shiwan=temp_data/100000+0x30 ;temp_data=temp_data%100000; /取余運算 wan=temp_data/10000+0x30 ; temp_data=temp_data%10000; /取余運算 qian=temp_data/1000+0x30 ; temp_data=temp_data%1000; /取余運算 bai=temp_data/100+0x30 ; temp_data=temp_data%10

15、0; /取余運算 shi=temp_data/10+0x30 ; temp_data=temp_data%10; /取余運算 ge=temp_data+0x30; void bmp085Convert(void) long ut; long up; long x1, x2, b5, b6, x3, b3, p; unsigned long b4, b7; long temperature; long pressure;float altitude; /* ut = bmp085ReadTemp(); ut = bmp085ReadTemp(); / 讀取溫度 up = bmp085ReadPr

16、essure(); up = bmp085ReadPressure(); / 讀取壓強 /*/ x1 = (long)ut - ac6) * ac5 >> 15; x2 = (long) mc << 11) / (x1 + md); b5 = x1 + x2; temperature = (b5 + 8) >> 4; /* conver085(temperature); lcd_show_char(1,0,bai); /LCD顯示，根據顯示位置修改 lcd_show_char(1,1,shi); lcd_show_char(1,3,ge); /* b6 =

17、b5 - 4000; x1 = (b2 * (b6 * b6 >> 12) >> 11; x2 = ac2 * b6 >> 11; x3 = x1 + x2; b3 = (long)ac1 * 4 + x3) + 2)/4; x1 = ac3 * b6 >> 13; x2 = (b1 * (b6 * b6 >> 12) >> 16; x3 = (x1 + x2) + 2) >> 2; b4 = (ac4 * (unsigned long) (x3 + 32768) >> 15; b7 = (unsi

18、gned long) up - b3) * (50000 >> OSS); if( b7 < 0x80000000) p = (b7 * 2) / b4 ; else p = (b7 / b4) * 2; x1 = (p >> 8) * (p >> 8); x1 = (x1 * 3038) >> 16; x2 = (-7357 * p) >> 16; pressure = p + (x1 + x2 + 3791) >> 4);conver085(pressure);lcd_show_char(2,4,shiwan);

19、 /LCD顯示，根據顯示位置修改 lcd_show_char(2,5,wan); lcd_show_char(2,6,qian); lcd_show_char(2,7,bai); lcd_show_char(2,9,shi);lcd_show_char(2,10,ge);/* altitude=44330.0*(1.0-pow(float)(pressure)/101325.0,1.0/5.255); /根據芯片手冊提供的公式計算海拔高度altitude *= 100; /轉換成厘米單位的高度值，調用時再換算成帶小數的高度值，提高精度 conver085(altitude);lcd_show_char(1,8,shiwan); /LCD顯示，根據顯示位置修改 lcd_show_char(1,9,wan); lcd_sh