前言

瑞薩RA MCU眾測寶典 | 串口之【RA-Eco-RA2L1】RTC日歷及串口設(shè)置時(shí)間

RA MCU眾測寶典 | PWM之【RA2L1】呼吸燈

RA MCU眾測寶典 | ADC/DAC之【RA2L1】DAC電壓輸出及ADC電壓采集實(shí)驗(yàn)

本次實(shí)驗(yàn)的目標(biāo)是把I2C相關(guān)的搞定，再嘗試驅(qū)動(dòng)SSD1306 0.96寸OLED屏幕以及BME280傳感器，最后將傳感器讀到的數(shù)據(jù)和實(shí)時(shí)時(shí)間顯示在屏幕上。

01

硬件部分

1

I2C協(xié)議簡介

I2C通訊協(xié)議（Inter-Integrated Circuit）由于它引腳少，硬件實(shí)現(xiàn)簡單，可擴(kuò)展性強(qiáng)，不需要USART、CAN等通訊協(xié)議的外部收發(fā)設(shè)備，現(xiàn)在被廣泛地使用在系統(tǒng)內(nèi)多個(gè)集成電路（IC）間的通訊。

在計(jì)算機(jī)科學(xué)里，大部分復(fù)雜的問題都可以通過分層來簡化。如芯片被分為內(nèi)核層和片上外設(shè)；瑞薩的FPS庫則是在寄存器與用戶代碼之間的軟件層。

對(duì)于通訊協(xié)議，我們也以分層的方式來理解，最基本的是把它分為物理層和協(xié)議層。物理層規(guī)定通訊系統(tǒng)中具有機(jī)械、電子功能部分的特性，確保原始數(shù)據(jù)在物理媒體的傳輸。協(xié)議層主要規(guī)定通訊邏輯，統(tǒng)一收發(fā)雙方的數(shù)據(jù)打包、解包標(biāo)準(zhǔn)。簡單來說物理層規(guī)定我們用嘴巴還是用肢體來交流，協(xié)議層則規(guī)定我們用中文還是英文來交流。

2

OLED屏幕

本次使用的屏幕是0.96寸4針I(yè)2C協(xié)議OLED屏幕，其驅(qū)動(dòng)IC為SSD1306，屏幕分辨率為128x64。

編程時(shí)參考的數(shù)據(jù)手冊(cè)，具體的修改參考軟件部分。

3

BME280溫濕度氣壓傳感器

BME280是一款由Bosch Sensortec開發(fā)的多功能環(huán)境傳感器，可同時(shí)精確測量溫度、濕度和氣壓，具有低功耗和小尺寸的特點(diǎn)，廣泛應(yīng)用于氣象監(jiān)測、室內(nèi)導(dǎo)航、健康監(jiān)測及物聯(lián)網(wǎng)等領(lǐng)域。

02

軟件部分

將先前03_RTC工程復(fù)制一份，重命名為04_OLED_BME280-I2C。

1

配置I2C

首先在e2s內(nèi)配置I2C

點(diǎn)擊可查看大圖

點(diǎn)擊可查看大圖

點(diǎn)擊可查看大圖

點(diǎn)擊可查看大圖

這里說明一下，在移植OLED驅(qū)動(dòng)庫時(shí)看到屏幕地址為0x78，即01111000，是包含讀寫位的（最低位）。而瑞薩這里是7位地址，不含讀寫位，因此要將0x78右移1位，即0x3C（0111100）。

確認(rèn)上面設(shè)置沒問題后，生成項(xiàng)目代碼。

03

編寫代碼

1

I2C通信相關(guān)

新建i2c.c和i2c.h文件。

i2c.h

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#ifndefI2C_H_#defineI2C_H_
externvolatilebool i2c_rx_complete;externvolatilebool i2c_tx_complete;
voidi2c_wait_rx();voidi2c_wait_tx();#endif

i2c.c

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#include"hal_data.h"#include"i2c.h"
volatilebool i2c_rx_complete =false;volatilebool i2c_tx_complete =false;uint16_ttimeout= 0;
voidiic_callback(i2c_master_callback_args_t *p_args){ if(p_args->event == I2C_MASTER_EVENT_RX_COMPLETE) { i2c_rx_complete =true; } elseif (p_args->event == I2C_MASTER_EVENT_TX_COMPLETE) { i2c_tx_complete =true; }}
voidi2c_wait_tx(){ timeout= 1000; while(!i2c_tx_complete &&timeout> 0) { timeout--; } i2c_tx_complete =false;}
voidi2c_wait_rx(){ timeout= 1000; while(!i2c_rx_complete &&timeout> 0) { timeout--; } i2c_rx_complete =false;}

由于瑞薩FSP庫的高集成度，我只需要編寫代碼實(shí)現(xiàn)回調(diào)函數(shù)iic_callback、等待發(fā)送函數(shù)i2c_wait_tx、等待接收i2c_wait_rx函數(shù)改變標(biāo)志位即可。

2

BME280操作相關(guān)

bme280.h

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#ifndefBME280_H_#defineBME280_H_#include"hal_data.h"#defineBME280_ID 0x60typedefstruct{ doublehumi, temp, press; boolinitialized;} BME_Struct;
voidBME280_Get_Data(BME_Struct *bme);voidBME280_Init(BME_Struct *bme);voidBME280_Write_then_Read(uint8_t*src,uint8_twrite_bytes,uint8_t*data_dest,uint8_tread_bytes);voidBME280_Trimming_Values();doubleBME280_compensate_T_double(int32_tadc_T);doubleBME280_compensate_P_double(int32_tadc_P);doublebme280_compensate_H_double(int32_tadc_H);
#endif/* BME280_H_ */

bme280.c

#include"bme280.h"#include"hal_data.h"#include"i2c.h"
uint16_tdig_T1;int16_tdig_T2;int16_tdig_T3;uint16_tdig_P1;int16_tdig_P2;int16_tdig_P3;int16_tdig_P4;int16_tdig_P5;int16_tdig_P6;int16_tdig_P7;int16_tdig_P8;int16_tdig_P9;
int8_tdig_H1;int16_tdig_H2;int8_tdig_H3;int16_tdig_H4;int16_tdig_H5;int8_tdig_H6;
voidBME280_Write_then_Read(uint8_t*src,uint8_twrite_bytes,uint8_t*data_dest,uint8_tread_bytes){ //臨時(shí)設(shè)置I2C從機(jī)地址為0x76 g_i2c_master0.p_api->slaveAddressSet(&g_i2c_master0_ctrl,0x76, I2C_MASTER_ADDR_MODE_7BIT); g_i2c_master0.p_api->write(&g_i2c_master0_ctrl, src, write_bytes,true); i2c_wait_tx(); g_i2c_master0.p_api->read(&g_i2c_master0_ctrl, data_dest, read_bytes,false); i2c_wait_rx(); g_i2c_master0.p_api->slaveAddressSet(&g_i2c_master0_ctrl,0x3C, I2C_MASTER_ADDR_MODE_7BIT);}
voidBME280_Init(BME_Struct *bme){ uint8_treg =0xD0; uint8_twrite_settings[7] = {0x00}; uint8_tread_data; BME280_Write_then_Read(?,1, &read_data,1); if(read_data != BME280_ID) { printf("Init BME280 Failed!\n"); bme->initialized =false; return; } else { bme->initialized =true; }
write_settings[0] =0xF2;// 設(shè)置濕度采集的寄存器 0xF2 write_settings[1] =0x05;// 00000 101 濕度 oversampling x16 write_settings[2] =0xF4;// 設(shè)置溫度采集、氣壓采集、工作模式的寄存器 0xF4 write_settings[3] =0x93;// 100 100 11 溫度和氣壓 oversampling x8，模式為normal write_settings[4] =0xF5;// 配置config寄存器 write_settings[5] =0x10;// 000 100 0 0 ，配置濾波器系數(shù)為16 g_i2c_master0.p_api->slaveAddressSet(&g_i2c_master0_ctrl,0x76, I2C_MASTER_ADDR_MODE_7BIT); g_i2c_master0.p_api->write(&g_i2c_master0_ctrl, &write_settings[0],6,false); i2c_wait_tx(); g_i2c_master0.p_api->slaveAddressSet(&g_i2c_master0_ctrl,0x3C, I2C_MASTER_ADDR_MODE_7BIT); R_BSP_SoftwareDelay(2, BSP_DELAY_UNITS_MILLISECONDS); // 校準(zhǔn)數(shù)據(jù) BME280_Trimming_Values();}
voidBME280_Trimming_Values(){ uint8_tdata[33] = { 0, }; uint8_treg =0x88; BME280_Write_then_Read(?,1, &data[0],24); R_BSP_SoftwareDelay(5, BSP_DELAY_UNITS_MILLISECONDS);// 適當(dāng)加延遲否則數(shù)據(jù)錯(cuò)誤 reg =0xA1; BME280_Write_then_Read(?,1, &data[24],1); R_BSP_SoftwareDelay(5, BSP_DELAY_UNITS_MILLISECONDS);// 適當(dāng)加延遲否則數(shù)據(jù)錯(cuò)誤 reg =0xE1; BME280_Write_then_Read(?,1, &data[25],7); R_BSP_SoftwareDelay(5, BSP_DELAY_UNITS_MILLISECONDS);// 適當(dāng)加延遲否則數(shù)據(jù)錯(cuò)誤
dig_T1 = (data[1] < dig_P1 = (data[7] < dig_H1 = data[24]; dig_H2 = (data[26] <>4)); dig_H6 = data[31];}
// Returns temperature in DegC, double precision. Output value of “51.23” equals 51.23 DegC.// t_fine carries fine temperature as global valuevolatilelongsignedint t_fine;doubleBME280_compensate_T_double(longsignedint adc_T){ doublevar1, var2, T; var1 = (((double)adc_T) /16384.0- ((double)dig_T1) /1024.0) * ((double)dig_T2); var2 = ((((double)adc_T) /131072.0- ((double)dig_T1) /8192.0) * (((double)adc_T) /131072.0- ((double)dig_T1) /8192.0)) * ((double)dig_T3); t_fine = (longsignedint)(var1 + var2); T = (var1 + var2) /5120.0; returnT;}// Returns pressure in Pa as double. Output value of “96386.2” equals 96386.2 Pa = 963.862 hPadoubleBME280_compensate_P_double(longsignedint adc_P){ doublevar1, var2, p; var1 = ((double)t_fine /2.0) -64000.0; var2 = var1 * var1 * ((double)dig_P6) /32768.0; var2 = var2 + var1 * ((double)dig_P5) *2.0; var2 = (var2 /4.0) + (((double)dig_P4) *65536.0); var1 = (((double)dig_P3) * var1 * var1 /524288.0+ ((double)dig_P2) * var1) /524288.0; var1 = (1.0+ var1 /32768.0) * ((double)dig_P1); if(var1 ==0.0) { return0;// avoid exception caused by division by zero } p =1048576.0- (double)adc_P; p = (p - (var2 /4096.0)) *6250.0/ var1; var1 = ((double)dig_P9) * p * p /2147483648.0; var2 = p * ((double)dig_P8) /32768.0; p = p + (var1 + var2 + ((double)dig_P7)) /16.0; returnp;}// Returns humidity in %rH as as double. Output value of “46.332” represents 46.332 % rHdoublebme280_compensate_H_double(longsignedint adc_H){ doublevar_H; var_H = (((double)t_fine) -76800.0); var_H = (adc_H - (((double)dig_H4) *64.0+ ((double)dig_H5) /16384.0* var_H)) * (((double)dig_H2) /65536.0* (1.0+ ((double)dig_H6) /67108864.0* var_H * (1.0+ ((double)dig_H3) /67108864.0* var_H))); var_H = var_H * (1.0- ((double)dig_H1) * var_H /524288.0); if(var_H >100.0) var_H =100.0; elseif(var_H voidBME280_Get_Data(BME_Struct *bme){ uint8_tdat[8] = {0}; uint32_tpress_t,temp_t,hum_t=0; uint8_treg =0xF7;
BME280_Write_then_Read(?,1, &dat[0],8); R_BSP_SoftwareDelay(2, BSP_DELAY_UNITS_MILLISECONDS); press_t= ((((uint32_t)dat[0] <>4)); temp_t= ((((uint32_t)dat[3] <>4)); hum_t= (((uint32_t)dat[6] < bme->temp =BME280_compensate_T_double(temp_t); bme->press =BME280_compensate_P_double(press_t) /100.0; bme->humi =bme280_compensate_H_double(hum_t);// printf("temp: %.2lf, humid: %.2lf, pressure: %.2lf\n", bme->temp, bme->humi, bme->press);}

BME280_compensate_T_double

bme280_compensate_H_double、

bme280_compensate_P_double

這三個(gè)函數(shù)分別為溫度、濕度、氣壓的補(bǔ)償算法函數(shù)，借鑒了BME280官方數(shù)據(jù)手冊(cè)內(nèi)給出的參考代碼。

bme280工作流程為

注意

在寫入+讀取函數(shù)后記得跟1~5ms的延時(shí)，再進(jìn)行下一步操作，否則會(huì)因?yàn)閎me280側(cè)的數(shù)據(jù)未準(zhǔn)備好，有極大概率讀取到錯(cuò)誤數(shù)據(jù)或讀不到數(shù)據(jù)。

3

OLED屏幕操作相關(guān)

oled.h

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#ifndefOLED_H_#defineOLED_H_
#include"hal_data.h"
#defineOLED_CMD 0 // 寫命令#defineOLED_DATA 1// 寫數(shù)據(jù)voidOLED_ClearPoint(uint8_tx,uint8_ty);voidOLED_ColorTurn(uint8_ti);voidOLED_DisplayTurn(uint8_ti);voidOLED_WR_Byte(uint8_tdat,uint8_tmode);voidOLED_DisPlay_On(void);voidOLED_DisPlay_Off(void);voidOLED_Refresh(void);voidOLED_Clear(void);voidOLED_DrawPoint(uint8_tx,uint8_ty,uint8_tt);voidOLED_DrawLine(uint8_tx1,uint8_ty1,uint8_tx2,uint8_ty2,uint8_tmode);voidOLED_DrawCircle(uint8_tx,uint8_ty,uint8_tr);voidOLED_ShowChar(uint8_tx,uint8_ty,uint8_tchr,uint8_tsize1);voidOLED_ShowString(uint8_tx,uint8_ty,uint8_t*chr,uint8_tsize1);voidOLED_ShowNum(uint8_tx,uint8_ty,uint32_tnum,uint8_tlen,uint8_tsize1);voidOLED_ShowChinese(uint8_tx,uint8_ty,uint8_tnum,uint8_tsize1);voidOLED_ScrollDisplay(uint8_tnum,uint8_tspace);voidOLED_ShowPicture(uint8_tx,uint8_ty,uint8_tsizex,uint8_tsizey,uint8_tBMP[],uint8_tmode);voidOLED_Init(void);
#endif

oled.c

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#include"oled.h"#include"oled_font.h"#include"i2c.h"volatileuint8_tOLED_GRAM[144][8];// 反顯函數(shù)voidOLED_ColorTurn(uint8_ti){ if(i ==0) { OLED_WR_Byte(0xA6, OLED_CMD);// 正常顯示 } if(i ==1) { OLED_WR_Byte(0xA7, OLED_CMD);// 反色顯示 }}// 屏幕旋轉(zhuǎn)180度voidOLED_DisplayTurn(uint8_ti){ if(i ==0) { OLED_WR_Byte(0xC8, OLED_CMD);// 正常顯示 OLED_WR_Byte(0xA1, OLED_CMD); } if(i ==1) { OLED_WR_Byte(0xC0, OLED_CMD);// 反轉(zhuǎn)顯示 OLED_WR_Byte(0xA0, OLED_CMD); }}// 發(fā)送一個(gè)字節(jié)// mode:數(shù)據(jù)/命令標(biāo)志 0,表示命令;1,表示數(shù)據(jù);voidOLED_WR_Byte(uint8_tdat,uint8_tmode){ uint8_tdata[2]; if(mode) { data[0] =0x40; } else { data[0] =0x00; } data[1] = dat; R_IIC_MASTER_Write(&g_i2c_master0_ctrl, data,2,false); i2c_wait_tx();}// 開啟OLED顯示voidOLED_DisPlay_On(void){ OLED_WR_Byte(0x8D, OLED_CMD);// 電荷泵使能 OLED_WR_Byte(0x14, OLED_CMD);// 開啟電荷泵 OLED_WR_Byte(0xAF, OLED_CMD);// 點(diǎn)亮屏幕}// 關(guān)閉OLED顯示voidOLED_DisPlay_Off(void){ OLED_WR_Byte(0x8D, OLED_CMD);// 電荷泵使能 OLED_WR_Byte(0x10, OLED_CMD);// 關(guān)閉電荷泵 OLED_WR_Byte(0xAE, OLED_CMD);// 關(guān)閉屏幕}// 更新顯存到OLEDvoidOLED_Refresh(void){ uint8_ti, n; for(i =0; i 0) incx =1;// 設(shè)置單步方向 elseif(delta_x ==0) incx =0;// 垂直線 else { incx =-1; delta_x = -delta_x; } if(delta_y >0) incy =1; elseif(delta_y ==0) incy =0;// 水平線 else { incy =-1; delta_y = -delta_x; } if(delta_x > delta_y) distance = delta_x;// 選取基本增量坐標(biāo)軸 else distance = delta_y; for(t =0; t < distance +?1; t++)? ? {? ? ? ? OLED_DrawPoint(uRow, uCol, mode);?// 畫點(diǎn)? ? ? ? xerr += delta_x;? ? ? ? yerr += delta_y;? ? ? ? if?(xerr > distance) { xerr -= distance; uRow += incx; } if(yerr > distance) { yerr -= distance; uCol += incy; } } // OLED_Refresh();}// x,y:圓心坐標(biāo)// r:圓的半徑voidOLED_DrawCircle(uint8_tx,uint8_ty,uint8_tr){ inta, b, num; a =0; b = r; while(2* b * b >= r * r) { OLED_DrawPoint(x + a, y - b,1); OLED_DrawPoint(x - a, y - b,1); OLED_DrawPoint(x - a, y + b,1); OLED_DrawPoint(x + a, y + b,1); OLED_DrawPoint(x + b, y + a,1); OLED_DrawPoint(x + b, y - a,1); OLED_DrawPoint(x - b, y - a,1); OLED_DrawPoint(x - b, y + a,1); a++; num = (a * a + b * b) - r * r;// 計(jì)算畫的點(diǎn)離圓心的距離 if(num >0) { b--; a--; } } // OLED_Refresh();}// 顯示字符 不建議直接使用，若要使用需要加上OLED_Refresh();更新到顯存voidOLED_ShowChar(uint8_tx,uint8_ty,uint8_tchr,uint8_tsize1){ uint8_ti, m, temp, size2, chr1; uint8_tx0 = x, y0 = y; // 計(jì)算字符的字節(jié)數(shù) if(size1 ==8) size2 =6; else size2 = (size1 /8+ ((size1 %8) ?1:0)) * (size1 /2);// 字體占用的字節(jié)數(shù) chr1 = chr -' ';// 偏移字符值，轉(zhuǎn)換為數(shù)組索引 for(i =0; i < size2; i++)? ? {? ? ? ? // 根據(jù)字體大小選擇相應(yīng)的字模? ? ? ? if?(size1 ==?8)? ? ? ? {? ? ? ? ? ? temp = asc2_0806[chr1][i];? ? ? ? }? ? ? ? elseif?(size1 ==?12)? ? ? ? {? ? ? ? ? ? temp = asc2_1206[chr1][i];? ? ? ? }? ? ? ? elseif?(size1 ==?16)? ? ? ? {? ? ? ? ? ? temp = asc2_1608[chr1][i];? ? ? ? }? ? ? ? elseif?(size1 ==?24)? ? ? ? {? ? ? ? ? ? temp = asc2_2412[chr1][i];? ? ? ? }? ? ? ? else? ? ? ? {? ? ? ? ? ? return;?// 字體不支持? ? ? ? }? ? ? ? for?(m =?0; m >=1; y++; } x++; if((size1 !=8) && ((x - x0) == size1 /2)) { x = x0; y0 = y0 +8; } y = y0; }}// 顯示字符串// x,y:起點(diǎn)坐標(biāo)// size1:字體大小//*chr:字符串起始地址voidOLED_ShowString(uint8_tx,uint8_ty,uint8_t*chr,uint8_tsize1){ while((*chr >=' ') && (*chr <=?'~'))?// 判斷是不是非法字符!? ? {? ? ? ? OLED_ShowChar(x, y, *chr, size1);? ? ? ? if?(size1 ==?8)? ? ? ? ? ? x +=?6;? ? ? ? else? ? ? ? ? ? x += size1 /?2;? ? ? ? chr++;? ? }? ? OLED_Refresh();}// m^nuint32_tOLED_Pow(uint8_t?m,?uint8_t?n){? ? uint32_t?result =?1;? ? while?(n--)? ? {? ? ? ? result *= m;? ? }? ? return?result;}// 顯示數(shù)字// x,y :起點(diǎn)坐標(biāo)// num :要顯示的數(shù)字// len :數(shù)字的位數(shù)// size:字體大小voidOLED_ShowNum(uint8_t?x,?uint8_t?y,?uint32_t?num,?uint8_t?len,?uint8_t?size1){? ? uint8_t?t, temp, m =?0;? ? if?(size1 ==?8)? ? ? ? m =?2;? ? for?(t =?0; t < len; t++)? ? {? ? ? ? temp = (num /?OLED_Pow(10, len - t -?1)) %?10;? ? ? ? if?(temp ==?0)? ? ? ? {? ? ? ? ? ? OLED_ShowChar(x + (size1 /?2?+ m) * t, y,?'0', size1);? ? ? ? }? ? ? ? else? ? ? ? {? ? ? ? ? ? OLED_ShowChar(x + (size1 /?2?+ m) * t, y, temp +?'0', size1);? ? ? ? }? ? }? ? OLED_Refresh();}voidOLED_ShowChinese(uint8_t?x,?uint8_t?y,?uint8_t?num,?uint8_t?size1){? ? uint8_t?m, temp;? ? uint8_t?x0 = x, y0 = y;? ? uint16_t?i, size3 = (size1 /?8?+ ((size1 %?8) ??1?:?0)) * size1;?// 計(jì)算一個(gè)字符對(duì)應(yīng)的字節(jié)數(shù)? ? uint8_t?mask; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?// 用來構(gòu)造顯示的掩碼? ? for?(i =?0; i < size3; i++)? ? {? ? ? ? if?(size1 ==?16)? ? ? ? {? ? ? ? ? ? temp = Hzk1[num][i];?// 獲取字形數(shù)據(jù)? ? ? ? }? ? ? ? else? ? ? ? {? ? ? ? ? ? return;?// 只處理 16x16 字體? ? ? ? }? ? ? ? for?(m =?0; m >=1;// 右移，處理下一個(gè)像素 y++; // 縱向位置移動(dòng) } x++;// 橫向位置移動(dòng) // 判斷是否換行 if((x - x0) == size1) { x = x0; y0 = y0 +8;// 換行時(shí)，y 坐標(biāo)增加 8 } y = y0;// 恢復(fù) y 坐標(biāo) } // 最后刷新整個(gè)顯示屏 OLED_Refresh();}// num 顯示漢字的個(gè)數(shù)// space 每一遍顯示的間隔voidOLED_ScrollDisplay(uint8_tnum,uint8_tspace){ uint8_ti, n, t =0, m =0, r; while(1) { if(m ==0) { OLED_ShowChinese(128,24, t,16);// 寫入一個(gè)漢字保存在OLED_GRAM[][]數(shù)組中 t++; } if(t == num) { for(r =0; r >=1; y++; } x++; if((x - x0) == sizex) { x = x0; y0 = y0 +8; } y = y0; } } OLED_Refresh();}// OLED的初始化voidOLED_Init(void){ OLED_WR_Byte(0xAE, OLED_CMD);//--turn off oled panel 關(guān)閉顯示 OLED_WR_Byte(0x00, OLED_CMD);//---set low column address OLED_WR_Byte(0x10, OLED_CMD);//---set high column address OLED_WR_Byte(0x40, OLED_CMD);//--set start line address Set Mapping RAM Display Start Line (0x00~0x3F) OLED_WR_Byte(0x81, OLED_CMD);//--set contrast control register OLED_WR_Byte(0xCF, OLED_CMD);// Set SEG Output Current Brightness OLED_WR_Byte(0xA1, OLED_CMD);//--Set SEG/Column Mapping 0xa0左右反置 0xa1正常 OLED_WR_Byte(0xC8, OLED_CMD);// Set COM/Row Scan Direction 0xc0上下反置 0xc8正常 OLED_WR_Byte(0xA6, OLED_CMD);//--set normal display OLED_WR_Byte(0xA8, OLED_CMD);//--set multiplex ratio(1 to 64) 設(shè)置驅(qū)動(dòng)路數(shù) OLED_WR_Byte(0x3f, OLED_CMD);//--1/64 duty OLED_WR_Byte(0xD3, OLED_CMD);//-set display offset Shift Mapping RAM Counter (0x00~0x3F) OLED_WR_Byte(0x00, OLED_CMD);//-not offset OLED_WR_Byte(0xd5, OLED_CMD);//--set display clock divide ratio/oscillator frequency OLED_WR_Byte(0x80, OLED_CMD);//--set divide ratio, Set Clock as 100 Frames/Sec OLED_WR_Byte(0xD9, OLED_CMD);//--set pre-charge period OLED_WR_Byte(0xF1, OLED_CMD);// Set Pre-Charge as 15 Clocks & Discharge as 1 Clock OLED_WR_Byte(0xDA, OLED_CMD);//--set com pins hardware configuration OLED_WR_Byte(0x12, OLED_CMD); OLED_WR_Byte(0xDB, OLED_CMD);//--set vcomh OLED_WR_Byte(0x30, OLED_CMD);// Set VCOM Deselect Level OLED_WR_Byte(0x20, OLED_CMD);//-Set Page Addressing Mode (0x00/0x01/0x02) OLED_WR_Byte(0x02, OLED_CMD);// OLED_WR_Byte(0x8D, OLED_CMD);//--set Charge Pump enable/disable OLED_WR_Byte(0x14, OLED_CMD);//--set(0x10) disable OLED_Clear(); OLED_WR_Byte(0xAF, OLED_CMD);}

tip

最開始OLED屏幕上顯示字的速度非常慢，幾乎是一個(gè)字一個(gè)字地往外蹦。

解決方法是開一個(gè)顯存數(shù)組OLED_GRAM，將內(nèi)容先緩存到顯存數(shù)組，再調(diào)用OLED_Refresh一次性地寫給OLED屏幕控制器。

4

修改hal_entry.c

在hal_entry.c開頭加入：

左右滑動(dòng)查看完整內(nèi)容

#include"hal_data.h"#include"debug_bsp_uart.h"#include"oled.h"#include"bme280.h"#include"rtc.h"#include
BME_Struct bme = {0,0,0,false};rtc_time_tget_time;

在hal_entry函數(shù)中加入：

滑動(dòng)查看完整內(nèi)容

Debug_UART9_Init();//SCI9 UART 調(diào)試串口初始化 g_i2c_master0.p_api->open(&g_i2c_master0_ctrl, &g_i2c_master0_cfg); BME280_Init(&bme); OLED_Init(); RTC_Init(); printf("I2C OLED屏幕+BME280獲取溫濕度實(shí)驗(yàn)\n"); printf("若要通過串口設(shè)置時(shí)間，請(qǐng)輸入類似time:20250126080910的字符串\n"); while(1) { uint8_t t1[50] ={0}, t2[50] ={0}, t3[50] ={0}, t4[50] ={0}; if(rtc_flag) { g_rtc0.p_api->calendarTimeGet(&g_rtc0_ctrl, &get_time);//獲取 RTC 計(jì)數(shù)時(shí)間 rtc_flag =0;// printf("%d年%d月%d日%d:%d:%d\n",// get_time.tm_year +1900, get_time.tm_mon +1, get_time.tm_mday,// get_time.tm_hour, get_time.tm_min, get_time.tm_sec);
sprintf((char *)t1,"%4d.%02d.%02d", get_time.tm_year +1900, get_time.tm_mon +1, get_time.tm_mday); sprintf((char *)t2,"%02d:%02d:%02d", get_time.tm_hour, get_time.tm_min, get_time.tm_sec);
if(bme.initialized) { BME280_Get_Data(&bme); sprintf((char *)t3,"%.1fC%.1f%%RH", bme.temp, bme.humi); sprintf((char *)t4,"%.1fhPa", bme.press); OLED_ShowString(12,32, t3,16);//顯示溫度濕度 OLED_ShowString(24,48, t4,16);//顯示氣壓 } OLED_ShowString(24,0, t1,16); //顯示年月日 OLED_ShowString(32,16, t2,16);//顯示時(shí)分秒
} if(uart_rx_complete_flag) { char *time; uart_rx_complete_flag =0; //解析設(shè)置時(shí)間的命令 e.g:time:20250126080910 // warning: 未添加錯(cuò)誤糾正算法，請(qǐng)輸入正確的時(shí)間，否則工作異常！ if(strncmp(rx_data,"time:",5) ==0) { time= rx_data +5; set_time.tm_year = ((time[0] -'0') *1000) + ((time[1] -'0') *100) + ((time[2] -'0') *10) + (time[3] -'0') -1900; set_time.tm_mon = ((time[4] -'0') *10) + (time[5] -'0') -1; set_time.tm_mday = ((time[6] -'0') *10) + (time[7] -'0'); set_time.tm_hour = ((time[8] -'0') *10) + (time[9] -'0'); set_time.tm_min = ((time[10] -'0') *10) + (time[11] -'0'); set_time.tm_sec = ((time[12] -'0') *10) + (time[13] -'0'); g_rtc0.p_api->calendarTimeSet(&g_rtc0_ctrl, &set_time); } else{ printf("若要通過串口設(shè)置時(shí)間，請(qǐng)輸入類似time:20250126080910的字符串\n"); } } }

這段程序?qū)崿F(xiàn)了每1秒刷新一次OLED屏幕上的時(shí)間和溫濕度氣壓數(shù)據(jù)，同時(shí)能從串口接收格式化的數(shù)據(jù)以設(shè)定時(shí)間。

04

下載測試

把編譯好的程序下載到開發(fā)板并復(fù)位。觀察到OLED屏幕上正確顯示了預(yù)設(shè)的時(shí)間和獲取到的溫濕度氣壓值。

可以打開串口助手，在發(fā)送框輸入time：20250128235958。

05

工程附件

（可以點(diǎn)擊“閱讀原文”或掃描下方二維碼/復(fù)制下方鏈接到瀏覽器下載附件查看完整代碼）

工程附件—OLED

https://bbs.elecfans.com/jishu_2474903_1_1.html

圖片演示

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