AT M 使用说明 SPI EEPROM STM.docx
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- 上传时间:2023-06-28
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AT M 使用说明 SPI EEPROM STM.docx
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ATM使用说明SPIEEPROMSTM
1.芯片访问规则符合AT25系列原则,可以找相关的例子,但是25M01目前没有
2.芯片工作原则,不考虑写保护问题,所有操作的第一步都是要发送写允许指令,然后重新片选有效,发送下一步的命令。
注意问题:
SPI的EEPROM的数据输出的原理是,在输入一个字节的同时输出一个字节,没有输入字节,就输出,所以,所谓的读数据,其实质是先发送一个数据,然后在接收一个数据。
操作如下:
(1)寄存器读
1)先片选,在发送写允许指令,片选无效
2)片选,发送读寄存器指令,读寄存器,片选无效
(2)寄存器写
1)先片选,在发送写允许指令,片选无效
2)片选,发送写寄存器指令,写数据,片选无效
(3)写数据
1)先片选,在发送写允许指令,片选无效
2)片选,发送写数据指令,写数据,片选无效
(4)读数据
1)先片选,在发送写允许指令,片选无效
2)片选,发送读数据指令,读数据,片选无效
注意:
STM32的SPI需要,每次都开启
voidSPI_EEPROM_Init(void)
{
SPI_InitTypeDefSPI_InitStructure;
GPIO_InitTypeDefGPIO_InitStructure;
/*EnableSPI1andGPIOclocks*/
/*!
SPI_FLASH_SPI_MISO_GPIO,SPI_FLASH_SPI_DETECT_GPIO andSPI_FLASH_SPI_SCK_GPIOPeriphclockenable*/ RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOC|RCC_APB2Periph_AFIO,ENABLE); /*! RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1,ENABLE); /*! SCK*/ =GPIO_Pin_5; =GPIO_Speed_50MHz; =GPIO_Mode_AF_PP; GPIO_Init(GPIOA,&GPIO_InitStructure); /*! MOSI*/ =GPIO_Pin_7; GPIO_Init(GPIOA,&GPIO_InitStructure); /*! MISO*/ =GPIO_Pin_6; =SPI_Direction_2Lines_FullDuplex; =SPI_Mode_Master; =SPI_DataSize_8b; //SPI模式3 //=SPI_CPOL_High; //=SPI_CPHA_2Edge; //SPI模式0 =SPI_CPOL_Low; =SPI_CPHA_1Edge; //软件片选 =SPI_NSS_Soft; //硬件片选 //=SPI_NSS_Hard; =SPI_BaudRatePrescaler_8;//72M/8=9Mhz,供电 =SPI_FirstBit_MSB; =7; SPI_Init(SPI1,&SPI_InitStructure); /*EnableSPI1*/ SPI_Cmd(SPI1,DISABLE); } /*********************************************ENDOFFILE**********************/ voidNSS_CS_ENABLE(uint8_tNSS) { if(NSS==1){NSS1_LOW();NSS2_HIGH();} elseif(NSS==2){NSS2_LOW();NSS1_HIGH();} } voidNSS_CS_DISABLE() { NSS1_HIGH(); NSS2_HIGH(); } voidSPI_WREN(uint8_tnss) { NSS_CS_ENABLE(nss); SPI_WriteByte(WREN); NSS_CS_DISABLE(); //Delay_ms (1); } voidSPI_WRDI(uint8_tnss) { NSS_CS_ENABLE(nss); SPI_WriteByte(WRDI); NSS_CS_DISABLE(); //Delay_ms (1); } voidSPI_EEPROM_WRITE_Start(void) { SPI_Cmd(SPI1,ENABLE); SPI_WREN (1); NSS_CS_ENABLE (1); SPI_WriteByte(WRSR); SPI_WriteByte(0X02); NSS_CS_DISABLE(); SPI_WREN (2); NSS_CS_ENABLE (2); SPI_WriteByte(WRSR); SPI_WriteByte(0X02); NSS_CS_DISABLE(); SPI_Cmd(SPI1,DISABLE); } voidSPI_EEPROM_WRITE_END(void) { SPI_Cmd(SPI1,ENABLE); SPI_WRDI (1); SPI_WRDI (2); SPI_Cmd(SPI1,DISABLE); } uint8_tSPI_WriteByte(uint8_tdata) { /*LoopwhileDRregisterinnotemplty*/ while(SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_TXE)==RESET); /*SendbytethroughtheSPI1peripheral*/ SPI_I2S_SendData(SPI1,data); /*Waittoreceiveabyte*/ while(SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_RXNE)==RESET); /*ReturnthebytereadfromtheSPIbus*/ returnSPI_I2S_ReceiveData(SPI1); } uint8_tSPI_ReadByte(void) { return(SPI_WriteByte(Dummy_Byte)); //while(SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_RXNE)==RESET); //returnSPI_I2S_ReceiveData(SPI1); } uint8_tAT25_GetStatus(uint8_tNSS) { uint8_ttmp=0; SPI_WREN(NSS); NSS_CS_ENABLE(NSS); SPI_WriteByte(RDSR); tmp=SPI_ReadByte(); NSS_CS_DISABLE(); returntmp; } voidAT25_WaitReady(uint8_tNSS) { while((0x01&AT25_GetStatus(NSS))! =0); } /* 单字节操作,读和写 */ uint8_tAT25_ReadByte(uint32_taddr) { uint8_ttmp; uint8_tnss=1; if(addr>=(uint32_t)(1024*128*2)) return0; if(addr>=(uint32_t)(1024*128)) {addr=addr-(uint32_t)(1024*128);nss=2;} elsenss=1; SPI_Cmd(SPI1,ENABLE); AT25_WaitReady(nss); SPI_WREN(nss); NSS_CS_ENABLE(nss); SPI_WriteByte(READ); SPI_WriteByte((uint8_t)((addr&0x010000)>>16));/*A16*/ SPI_WriteByte((uint8_t)((addr&0x00FF00)>>8));/*A15-A8*/ SPI_WriteByte((uint8_t)(addr&0x0000FF));/*A7-A0*/ tmp=SPI_ReadByte(); NSS_CS_DISABLE(); SPI_Cmd(SPI1,DISABLE); returntmp; } voidAT25_WriteByte(uint8_tdata,uint32_taddr) { uint8_tnss=1; uint32_ttt=1024*128*2; if(addr>=tt) return; if(addr>=(uint32_t)(1024*128)) {addr=addr-(uint32_t)(1024*128);nss=2;} elsenss=1; SPI_Cmd(SPI1,ENABLE); AT25_WaitReady(nss); SPI_WREN(nss); NSS_CS_ENABLE(nss); SPI_WriteByte(WRITE); SPI_WriteByte((uint8_t)((addr&0x010000)>>16));/*A16*/ SPI_WriteByte((uint8_t)((addr&0x00FF00)>>8));/*A15-A8*/ SPI_WriteByte((uint8_t)(addr&0x0000FF));/*A7-A0*/ SPI_WriteByte(data); NSS_CS_DISABLE(); SPI_Cmd(SPI1,DISABLE); } ////////////多字节操作 /** *@brief将缓冲区中的数据写到I2CEEPROM中 *@param *@argpBuffer: 缓冲区指针 *@argWriteAddr: 写地址 *@argNumByteToWrite: 写的字节数 *@retval无 */ voidSPI_EE_BufferWrite(u8*pBuffer,u32WriteAddr,u16NumByteToWrite,uint8_tNSS) { u32NumOfPage=0,NumOfSingle=0,Addr=0,count=0; Addr=WriteAddr%I2C_PageSize; count=I2C_PageSize-Addr; NumOfPage=NumByteToWrite/I2C_PageSize; NumOfSingle=NumByteToWrite%I2C_PageSize; /*IfWriteAddrisI2C_PageSizealigned*/ if(Addr==0) { /*IfNumByteToWrite if(NumOfPage==0) { SPI_EE_PageWrite(pBuffer,WriteAddr,NumOfSingle,NSS); } /*IfNumByteToWrite>I2C_PageSize*/ else { while(NumOfPage--) { SPI_EE_PageWrite(pBuffer,WriteAddr,I2C_PageSize,NSS); WriteAddr+=I2C_PageSize; pBuffer+=I2C_PageSize; } if(NumOfSingle! =0) { SPI_EE_PageWrite(pBuffer,WriteAddr,NumOfSingle,NSS); } } } /*IfWriteAddrisnotI2C_PageSizealigned*/ else { /*IfNumByteToWrite if(NumOfPage==0) { SPI_EE_PageWrite(pBuffer,WriteAddr,NumOfSingle,NSS); } /*IfNumByteToWrite>I2C_PageSize*/ else { NumByteToWrite-=count; NumOfPage=NumByteToWrite/I2C_PageSize; NumOfSingle=NumByteToWrite%I2C_PageSize; if(count! =0) { SPI_EE_PageWrite(pBuffer,WriteAddr,count,NSS); WriteAddr+=count; pBuffer+=count; } while(NumOfPage--) { SPI_EE_PageWrite(pBuffer,WriteAddr,I2C_PageSize,NSS); WriteAddr+=I2C_PageSize; pBuffer+=I2C_PageSize; } if(NumOfSingle! =0) { SPI_EE_PageWrite(pBuffer,WriteAddr,NumOfSingle,NSS); } } } } /** *@brief在EEPROM的一个写循环中可以写多个字节,但一次写入的字节数 *不能超过EEPROM页的大小,AT24C02每页有8个字节 *@param *@argpBuffer: 缓冲区指针 *@argWriteAddr: 写地址 *@argNumByteToWrite: 写的字节数 *@retval无 */ voidSPI_EE_PageWrite(u8*pBuffer,u32WriteAddr,u16NumByteToWrite,uint8_tNSS) { SPI_Cmd(SPI1,ENABLE); AT25_WaitReady(NSS); SPI_WREN(NSS); NSS_CS_ENABLE(NSS); SPI_WriteByte(WRITE); SPI_WriteByte((uint8_t)((WriteAddr&0x010000)>>16));/*A16*/ SPI_WriteByte((uint8_t)((WriteAddr&0x00FF00)>>8));/*A15-A8*/ SPI_WriteByte((uint8_t)(WriteAddr&0x0000FF));/*A7-A0*/ /*Whilethereisdatatobewritten*/ while(NumByteToWrite--) { /*Sendthecurrentbyte*/ SPI_WriteByte(*pBuffer); /*Pointtothenextbytetobewritten*/ pBuffer++; } /*SendSTOPcondition*/ NSS_CS_DISABLE(); SPI_Cmd(SPI1,DISABLE); } /** *@brief从EEPROM里面读取一块数据 *@param *@argpBuffer: 存放从EEPROM读取的数据的缓冲区指针 *@argWriteAddr: 接收数据的EEPROM的地址 *@argNumByteToWrite: 要从EEPROM读取的字节数 *@retval无 */ voidSPI_EE_BufferRead(u8*pBuffer,u32ReadAddr,u16NumByteToRead,uint8_tNSS) { uint8_tnss=NSS; SPI_Cmd(SPI1,ENABLE); AT25_WaitReady(nss); SPI_WREN(NSS); NSS_CS_ENABLE(nss); SPI_WriteByte(READ); SPI_WriteByte((uint8_t)((ReadAddr&0x010000)>>16));/*A16*/ SPI_WriteByte((uint8_t)((ReadAddr&0x00FF00)>>8));/*A15-A8*/ SPI_WriteByte((uint8_t)(ReadAddr&0x0000FF));/*A7-A0*/ /*Whilethereisdatatoberead*/ while(NumByteToRead) { *pBuffer=SPI_ReadByte(); pBuffer++; NumByteToRead--; } /*EnableAcknowledgementtobereadyforanotherreception*/ NSS_CS_DISABLE(); SPI_Cmd(SPI1,DISABLE); } //*****wdz*******// voidSPI_EE_BufferWrite2(u8*pBuffer,u32WriteAddr,u16NumByteToWrite) { u32temp=WriteAddr+NumByteToWrite-1; u32number=WriteAddr+NumByteToWrite-1024*128; if(temp<1024*128) { SPI_EE_BufferWrite(pBuffer,WriteAddr,NumByteToWrite,1); } elseif(WriteAddr<1024*128&&temp>=1024*128) { SPI_EE_BufferWrite(pBuffer,WriteAddr,NumByteToWrite-number,1); SPI_EE_BufferWrite(pBuffer+NumByteToWrite-number,0,number,2); } elseif(WriteAddr>=1024*128) { SPI_EE_BufferWrite(pBuffer,WriteAddr-1024*128,NumByteToWrite,2); } } voidSPI_EE_BufferRead2(u8*pBuffer,u32ReadAddr,u16NumByteToRead) { u32temp=ReadAddr+NumByteToRead-1; u32number=ReadAddr+NumByteToRead-1024*128; if(temp<1024*128) { SPI_EE_BufferRead(pBuffer,ReadAddr,NumByteToRead,1); } elseif(ReadAddr<1024*128&&temp>=1024*128) { SPI_EE_BufferRead(pBuffer,ReadAddr,NumByteToRead-number,1); SPI_EE_BufferRead(pBuffer+NumByteToRead-number,0,number,2); } elseif(ReadAddr>=1024*128) { SPI_EE_BufferRead(pBuffer,ReadAddr-1024*128,NumByteToRead,2); } } voidSPI_Read_status(void) { uint8_tmygetbyte; SPI_Cmd(SPI1,ENABLE); SPI_WREN (1); NSS1_LOW(); SPI_WriteByte(RDSR); mygetbyte=SPI_ReadByte(); USART_printf(USART3,"\r\nST1=%d",mygetbyte); SPI_WREN (2); NSS2_LOW(); SPI_WriteByte(RDSR); mygetbyte=SPI_ReadByte(); USART_printf(USART3,"\r\nST2=%d",mygetbyte); }
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