8、GUI芯片模块

8.1 SPI 通信

8.1.1  引脚介绍

图3.1.1是普通SPI连接图，在使用SPI通信，HOLD引脚和WP脚需要接2K电阻到VCC。

图3.1.1

 

8.1.2 GUI  芯片指令

 

图3.1.2操作存储芯片指令，可供客户写驱动做参考

 

8.1.3 SPI驱动程序

 

 

/**

* @brief write a byte to flash

* @param data: data to write

* @retval flash return data

*/

uint8_t spi_byte_write(uint8_t data)

{

uint8_t brxbuff;

spi_i2s_dma_transmitter_enable(SPI4, FALSE);

spi_i2s_dma_receiver_enable(SPI4, FALSE);

spi_i2s_data_transmit(SPI4, data);

while(spi_i2s_flag_get(SPI4, SPI_I2S_RDBF_FLAG) == RESET);

brxbuff = spi_i2s_data_receive(SPI4);

while(spi_i2s_flag_get(SPI4, SPI_I2S_BF_FLAG) != RESET);

return brxbuff;

}

 

/**

* @brief read a byte to flash

* @param none

* @retval flash return data

*/

uint8_t spi_byte_read(void)

{

return (spi_byte_write(FLASH_SPI_DUMMY_BYTE));

}

/**

* @brief read data from flash

* @param pbuffer: the pointer for data buffer

* @param read_addr: the address where the data is read

* @param length: buffer length

* @retval none

*/

void spiflash_read(uint8_t *pbuffer, uint32_t read_addr, uint32_t length)

{

FLASH_CS_LOW();

spi_byte_write(0x03); /* send instruction 0x03普通读取*/

spi_byte_write((uint8_t)((read_addr) >> 16)); /* send 24-bit address */

spi_byte_write((uint8_t)((read_addr) >> 8));

spi_byte_write((uint8_t)read_addr);

//spi_byte_write((uint8_t)0xff);//使用0x0B快速读取时需额外发送一个字节

spi_bytes_read(pbuffer, length);

FLASH_CS_HIGH();

}

/**

* @brief erase a sector data

* @param erase_addr: sector address to erase

* @retval none

*/

void spiflash_sector_erase(uint32_t erase_addr)

{

spiflash_write_enable();

 

spiflash_write_enable();

spiflash_wait_busy();

FLASH_CS_LOW();

spi_byte_write(0x20);//擦除指令

spi_byte_write((uint8_t)((erase_addr) >> 16));

spi_byte_write((uint8_t)((erase_addr) >> 8));

spi_byte_write((uint8_t)erase_addr);

FLASH_CS_HIGH();

spiflash_wait_busy();

}

/**

* @brief read data continuously

* @param pbuffer: buffer to save data

* @param length: buffer length

* @retval none

*/

void spi_bytes_read(uint8_t *pbuffer, uint32_t length)

{

while(length--)

{

while(spi_i2s_flag_get(SPI4, SPI_I2S_TDBE_FLAG) == RESET);

spi_i2s_data_transmit(SPI4, 0xa5);//随意值皆可

while(spi_i2s_flag_get(SPI4, SPI_I2S_RDBF_FLAG) == RESET);

*pbuffer = spi_i2s_data_receive(SPI4);

pbuffer++;

}

}

/**

* @brief read device id

* @param none

* @retval device id

*/

uint16_t spiflash_read_id(void)

{

uint16_t wreceivedata = 0;

FLASH_CS_LOW();

spi_byte_write(0x90);//0x90读取id指令

spi_byte_write(0x00);

spi_byte_write(0x00);

spi_byte_write(0x00);

wreceivedata |= spi_byte_read() << 8;

wreceivedata |= spi_byte_read();

FLASH_CS_HIGH();

return wreceivedata;

}