Shanghai Hangxin ACM32G103 development board study notes 10 (OLED displays temperature and humidity information)

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Shanghai Hangxin ACM32G103 development board study notes 10 (OLED displays temperature and humidity information) [Copy link]

 

## 12: OLED display uses 0.96-inch OLED with IIC interface to display information data. High resolution: 128x64 (same resolution as 12864, high PPI), wide voltage power supply (3V~5V), compatible with 3.3V and 5V level logic, no level conversion chip required. ### 12.1: Hardware design The product interface is defined as follows:  The corresponding motherboard interface:  The corresponding SCL pin is PA5. The SDA pin is PA6. ### 12.2: The software design group uses the hardware IIC interface to realize the OLED display. I will use software simulation IIC to realize it. 1: First define the GPIO pin information. #define DRV_OLED_GPIO GPIOA #define DRV_OLED_SCL_PIN GPIO_PIN_5 #define DRV_OLED_SDA_PIN GPIO_PIN_6 #define DRV_OLED_MODE GPIO_MODE_OUTPUT_PP #define DRV_OLED_PULL GPIO_PULLUP #define DRV_OLED_DRIVE GPIO_DRIVE_LEVEL3 #define DRV_OLED_ALTERNATE GPIO_FUNCTION_0 #define DRV_OLED_CLK_ENABLE() __RCC_GPIOD_CLK_ENABLE() void I2C_Write_SDA(GPIO_PinState H_L) { GPIO_WriteBit(DRV_OLED_GPIO,DRV_OLED_SDA_PIN,H_L); } void I2C_Write_SCL(GPIO_PinState H_L) { GPIO_WriteBit(DRV_OLED_GPIO,DRV_OLED_SCL_PIN,H_L); } #define OLED_READ_SDA GPIO_ReadPin(DRV_OLED_GPIO,DRV_O LED_SDA_PIN) ``` 2: Configure OLED pin input and output ```C //Initialize IIC void OLED_IIC_Init(void) { GPIO_InitTypeDef GPIO_InitStruct; /* Enable Clock */ DRV_OLED_CLK_ENABLE(); GPIO_InitStruct.Pin = DRV_OLED_SCL_PIN|DRV_OLED_SDA_PIN; GPIO_InitStr; uct.Mode = DRV_OLED_MODE; GPIO_InitStruct.Pull = DRV_OLED_PULL; GPIO_InitStruct.Drive = DRV_OLED_DRIVE; GPIO_InitStruct.Alternate = DRV_OLED_ALTERNATE; GPIO_Init(DRV_OLED_GPIO, &GPIO_InitStruct); GPIO_WriteBit(DRV_OLED_GPIO, DRV_OLED_SCL_PIN , GPIO_PIN_SET); GPIO_WriteBit(DRV_OLED_GPIO, DRV_OLED_SDA_PIN,GPIO_PIN_SET); } ``` Then simulate the IIC timing: ```C //Generate IIC start signal void OLED_IIC_Start(void) { OLED_SDA_OUT(); //sda line output I2C_Write_SDA(GPIO_PIN_SET); I2C_Write_SCL(GPIO_PIN_SET); delay_us(4); I2C_Write_SDA(GPIO_PIN_RESET); delay_us(4); I2C_Write_SCL(GPIO_PIN_RESET); } //Generate IIC stop signal void OLED_IIC_Stop(void) { OLED_SDA_OUT();//sda line output I2C_Write_SCL(GPIO_PIN_RESET); I2C_Write_SDA(GPIO_PIN_RESET); delay_us(4); I2C_Write_SCL(GPIO_PIN_SET); I2C_Write_SDA(GPIO_PIN_SET); delay_us(4); } //Wait for the response signal to arrive //Return value: 1, receiving the response failed // 0, receiving the response successfully u8 OLED_IIC_Wait_Ack(void) { u8 ucErrTime=0; OLED_SDA_IN(); //SDA is set to input I2C_Write_SDA(GPIO_PIN_SET); delay_us(1); I2C_Write_SCL(GPIO_PIN_SET); delay_us(1); while(OLED_READ_SDA) { ucErrTime++; if(ucErrTime>250) { OLED_IIC_Stop(); return 1; } } I2C_Write_SCL(GPIO_PIN_RESET); return 0; } //Generate ACK response void OLED_IIC_Ack(void) { I2C_Write_SCL(GPIO_PIN_RESET); OLED_SDA_OUT(); I2C_Write_SDA(GPIO_PIN_RESET); delay_us(2); I2C_Write_SCL(GPIO_PIN_SET); delay_us(2); I2C_Write_SCL(GPIO_PIN_RESET); } //Do not generate ACK response void OLED_IIC_NAck(void) { I2C_Write_SCL(GPIO_PIN_RESET); OLED_SDA_OUT(); I2C_Write_SDA(GPIO_PIN_SET); delay_us(2); I2C_Write_SCL(GPIO_PIN_SET); delay_us(2); I2C_Write_SCL(GPIO_PIN_RESET); } //IIC sends a byte //Returns whether the slave has a response //1, yes //0, no response void OLED_IIC_Send_Byte(u8 txd) { u8 t; OLED_SDA_OUT(); I2C_Write_SCL(GPIO_PIN_RESET); for(t=0;t<8;t++) { I2C_Write_SDA((txd&0x80)>>7); txd<<=1; delay_us(2); I2C_Write_SCL(GPIO_PIN_SET); delay_us(2); I2C_Write_SCL(GPIO_PIN_ RESET); delay_us(2); } OLED_IIC_Wait_Ack(); } //Read 1 byte, when ack=1, send ACK, ack=0, send nACK u8 OLED_IIC_Read_Byte(unsigned char ack) { unsigned char i,receive=0; OLED_SDA_IN();//SDA is set as input for(i=0;i<8;i++) { I2C_Write_SCL(GPIO_PIN_RESET); delay_us(2); I2C_Write_SCL(GPIO_PIN_SET); receive<<=1; if(OLED_READ_SDA)receive++; delay_us(1); } if (!ack) OLED_IIC_NAck();//Send nACK else OLED_IIC_Ack(); //Send ACK return receive; } ``` 3: OLED initialization```C /**************** ******OLED initialization************************************/ void OLED_Init(void) { delay_ms (500); //The delay here is very important OLED_WrCmd(0xae);//--turn off oled panel OLED_WrCmd(0x00);//---set low column address OLED_WrCmd(0x10);//-- -set high column address OLED_WrCmd(0x40);//--set start line address Set Mapping RAM Display Start Line (0x00~0x3F) OLED_WrCmd(0x81);//--set contrast control register OLED_WrCmd(Brightness); // Set SEG Output Current Brightness OLED_WrCmd(0xa1);//--Set SEG/Column Mapping 0xa0 left and right inversion 0xa1 normal OLED_WrCmd(0xc8);//Set COM/Row Scan Direction 0xc0 up and down inversion 0xc8 normal OLED_WrCmd(0xa6);//--set normal display OLED_WrCmd(0xa8);//--set multiplex ratio(1 to 64) OLED_WrCmd(0x3f);//--1/64 duty OLED_WrCmd(0xd3);//-set display offset Shift Mapping RAM Counter (0x00~0x3F ) OLED_WrCmd(0x00);//-not offset OLED_WrCmd(0xd5);//--set display clock divide ratio/oscillator frequency OLED_WrCmd(0x80);//--set divide ratio, Set Clock as 100 Frames/Sec OLED_WrCmd(0xd9);//--set pre-charge period OLED_WrCmd(0xf1);//Set Pre-Charge as 15 Clocks & Discharge as 1 Clock OLED_WrCmd(0xda);//--set com pins hardware configuration OLED_WrCmd(0x12); OLED_WrCmd(0xdb);//--set vcomh OLED_WrCmd(0x40);//Set VCOM Deselect Level OLED_WrCmd(0x20);/ /-Set Page Addressing Mode (0x00/0x01/0x02) OLED_WrCmd(0x02);// OLED_WrCmd(0x8d);//--set Charge Pump enable/disable OLED_WrCmd(0x14);//--set(0x10) disable OLED_WrCmd(0xa4);// Disable Entire Display On (0xa4/0xa5) OLED_WrCmd(0xa6);// Disable Inverse Display On (0xa6/a7) OLED_WrCmd(0xaf);//--turn on oled panel OLED_Fill(0x00); //Initial clear screen OLED_Set_Pos(0,0); } ``` 4: Chinese character display Use the character conversion tool PCtoLCD2002 to convert the information to be displayed It is a string;  The specific characters are as follows: ```C typedef struct { unsigned char Index[2]; unsigned char Msk[32]; } typFNT_GB16; static const typFNT_GB16 tfont16[] = { "热",0x10,0x60,0x02,0x8C,0x00,0x00,0xFE,0x92,0x92, 0x92,0x92,0x92,0xFE,0x00,0x00,0x00, 0x04,0x04,0x7E,0x01,0x40,0x7E,0x42,0x42,0x7E,0x42,0x7E,0x42,0x42,0x7E,0x40,0x00,/*"Temperature ",3*/ "degree",0x00,0x00,0xFC,0x24,0x24,0x24,0xFC,0x25,0x26,0x24,0xFC,0x24,0x24,0x24,0x04,0x00, 0x40,0x30,0x8F,0x80,0x84,0x4C,0x55, 0x25,0x25,0x25,0x55,0x4C,0x80,0x80,0x80,0x00,/*"degree",4*/ "Wet",0x10,0x60,0x02,0x8C,0x00,0xFE,0x92,0x92,0x92,0x92,0x92,0x92,0xFE,0x00,0x00,0x00, 0x04,0x04,0x7E,0x01,0x44,0x48,0x50, 0x7F,0x40,0x40,0x7F,0x50,0x48,0x44,0x40,0x00,/*"wet",2*/ } ``` Write a character display function: ```C /********* ************************************************** ******************* Function description: Display a single 16x16 Chinese character Entry data: x, y display coordinates *s Chinese character to be displayed sizey font size mode: How many Chinese characters does string S have? Return value: None ****************************************** ******************************************/ void LCD_ShowChinese16x16(uint16_t x, uint16_t y,uint8_t *s, uint8_t sizey) { uint8_t i= 0; uint16_t k; uint16_t HZnum;//Number of Chinese characters HZnum = sizeof(tfont16) / sizeof(typFNT_GB16); //Count the number of Chinese characters for(k = 0; k < HZnum; k++) { if ((tfont16[k].Index[0] == *(s)) && (tfont16[k].Index[1] == *(s + 1))) { OLED_Set_Pos(x,y); for(i = 0; i < sizey; i++) { OLED_WrDat(tfont16[k].Msk[i]); } OLED_Set_Pos(x,y+1); for(i = 0; i < sizey; i++) { OLED_WrDat(tfont16[k].Msk[i+sizey]); } } } } ``` The specific acquisition of temperature and humidity data will not be expanded. ### 12.3: Test result output The acquired temperature and humidity information is displayed through OLED: