江科大学习笔记 _14.软件SPI





W25Q64:地址宽度24位,3字节 8M->块->扇区->页
8 * 1024 *1024 范围:00 00 00H--7F FF FFH (8MB)
8M分为128个块,每个块(64K) 块0-块127,
(8*1024 *1024 /64*1024) = 128 范围:xx 00 00 H--xx FF FFH(64KB)
64K分为16个扇区,每个扇区(4k),扇区0--扇区15
(64*1024/4*1024) = 16 范围:xx x0 00h -- xx xF FFh (4KB)
4K分为16个页,每个页(256字节),页0--页15
(4*1024/256) = 16 范围:xx xx 00h -- xx xx FFh (256)

STM32单片机为主机,W25Q64为从机
CS:片选
DO:从机输出
CLK:时钟
DI:从机输入
void MySPI_Init(void)//初始化
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_7;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IPU;
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStruct);
MySPI_W_SS(1);
MySPI_W_SCK(0);
}
封装引脚
void MySPI_W_SS(uint8_t BitValue)
{
GPIO_WriteBit(SPI_Port,SS,(BitAction)BitValue);
}
void MySPI_W_SCK(uint8_t BitValue)
{
GPIO_WriteBit(SPI_Port,SCK,(BitAction)BitValue);
}
void MySPI_W_MOSI(uint8_t BitValue)
{
GPIO_WriteBit(SPI_Port,MOSI,(BitAction)BitValue);
}
uint8_t MySPI_R_MISO(void)
{
return (GPIO_ReadInputDataBit(SPI_Port,MISO));
}

void MySPI_Start(void)
{
MySPI_W_SS(0);
}
void MySPI_Stop(void)
{
MySPI_W_SS(1);
}

uint8_t MySPI_SwapByte(uint8_t ByteSend)
{
uint8_t ByteReceive = 0x00;
for(int8_t i = 7; i >= 0; i--)
{
//上升沿前,主机移出数据
MySPI_W_MOSI(ByteSend & (1 << i));
MySPI_W_SCK(1);
//上升沿时,从机会把MOSI数据读走
(第一个边沿移出数据)
//下降沿前(第二个边沿),主机读入数据
(第二个边沿移入数据)
if(MySPI_R_MISO() == 1){ByteReceive |= (1 << i);}
MySPI_W_SCK(0);
}
return ByteReceive;
}
W25Q64
void W25Q64_Init(void)
{
MySPI_Init();
}
void W25Q64_ReadID(uint8_t *MID, uint16_t *DID)
{
MySPI_Start();
MySPI_SwapByte(W25Q64_JEDEC_ID);//发W25Q64读ID号指令
//从机返回3个ID数据
*MID = MySPI_SwapByte(W25Q64_DUMMY_BYTE);//用0XFF读出寄存器中的厂商ID
*DID = MySPI_SwapByte(W25Q64_DUMMY_BYTE);//用0XFF读出寄存器中的设备ID高8位
*DID = (*DID << 8)|MySPI_SwapByte(W25Q64_DUMMY_BYTE);//用0XFF读出寄存器中的设备ID低8位,拼接
MySPI_Stop();
}
void W25Q64_WriteEnable(void)
{
MySPI_Start();
MySPI_SwapByte(W25Q64_WRITE_ENABLE);
MySPI_Stop();
}
void W25Q64_WaitBusy(void)
{
uint32_t TimeOut = 10000;
MySPI_Start();
MySPI_SwapByte(W25Q64_READ_STATUS_REGISTER_1);
while( (MySPI_SwapByte(W25Q64_DUMMY_BYTE) & 0x01) == 0x01)//等待BUSY位为0
{ //超时检测
TimeOut--;
if(TimeOut == 0)
break;
}
MySPI_Stop();
}
void W25Q64_PageProgram(uint32_t Address, uint8_t *DataArray, uint16_t Count)
{
uint16_t i;
W25Q64_WriteEnable();//写使能
MySPI_Start();
MySPI_SwapByte(W25Q64_PAGE_PROGRAM);
MySPI_SwapByte(Address >> 16);
MySPI_SwapByte(Address >> 8);
MySPI_SwapByte(Address);
for(i = 0; i < Count; i++)
{
MySPI_SwapByte(DataArray[i]);
}
MySPI_Stop();
W25Q64_WaitBusy();//等待busy位
}
//擦除扇区
void W25Q64_SectorErase(uint32_t Address)
{
W25Q64_WriteEnable();//写使能
MySPI_Start();
MySPI_SwapByte(W25Q64_SECTOR_ERASE_4KB);
MySPI_SwapByte(Address >> 16);
MySPI_SwapByte(Address >> 8);
MySPI_SwapByte(Address);
MySPI_Stop();
W25Q64_WaitBusy();//等待busy位
}
//读数据
void W25Q64_ReadData(uint32_t Address, uint8_t *DataArray, uint32_t Count)
{
uint32_t i;
MySPI_Start();
MySPI_SwapByte(W25Q64_READ_DATA);
MySPI_SwapByte(Address >> 16);
MySPI_SwapByte(Address >> 8);
MySPI_SwapByte(Address);
for(i = 0; i < Count; i++)
{
DataArray[i] = MySPI_SwapByte(W25Q64_DUMMY_BYTE);
}
MySPI_Stop();
}