int cmd_spi(int argc, char * const argv[])
{
struct w25qxx_init_t init;
uint32_t i, buf_size;
static uint8_t buf[256];
struct w25qxx_attr_t w25qxx;
init.delayms = DelayMs;
init.get_reamin = _get_reamin;
init.xfer = xfer;
SPI_QuickInit(SPI0_MOSI_PA7_MISO_PA6, kSPI_CPOL1_CPHA1, 100*1000);//配置PTA7为MOSI PTA6为MISO, 波特率为100K，但是实际波特率要根据匹配出来的寄存器值算，有些误差
GPIO_QuickInit(HW_GPIOA, 5, kGPIO_Mode_OPP); //PTA5 SS
GPIO_WriteBit(HW_GPIOA, 5, 1);
PORT_PinMuxConfig(HW_GPIOB,0,kPinAlt3); //PTB0 SCK
w25qxx_init(&init); //外部flash初始化
w25qxx_get_attr(&w25qxx);
buf_size = sizeof(buf);
/*读取外部flash256个字节*/
printf("reading page...\n");
w25qxx_read(0, buf, buf_size);
print_buf(buf,PAGE_SIZE);
/*擦除整个外部flash芯片*/
printf("erase all chips...\r\n");
w25qxx_erase_chip();
printf("erase complete\r\n");
/*读取外部flash256个字节*/
printf("reading page...\n");
w25qxx_read(0, buf, buf_size);
print_buf(buf,PAGE_SIZE);
/*编程外部flash256个字节*/
printf("programing a page...\n");
for(i=0;i<256;i++)
buf[i] = i;
w25qxx_write(0, buf, buf_size);
printf("clearing buffer..\n");
for(i=0;i<256;i++)
buf[i] = 0;
/*读取外部flash256个字节*/
printf("reading page...\n");
w25qxx_read(0, buf, buf_size);
print_buf(buf,PAGE_SIZE);
printf("demo end.\n");
return 0;
}
//向芯片写数据
int w25qxx_write(uint32_t addr, uint8_t *buf, uint32_t len)
{
uint32_t secpos;
uint16_t secoff;
uint16_t secremain;
uint16_t i;
uint8_t * mem_pool;
mem_pool = SPI_FLASH_BUFFER;
secpos = addr/4096;//扇区地址
secoff = addr%4096;//在扇区内的偏移
secremain = 4096-secoff;//扇区剩余空间大小
if(len <= secremain)secremain = len;//不大于4096个字节
while(1)
{
w25qxx_read(secpos*4096, mem_pool, 4096); //读出整个扇区的内容
for(i = 0; i < secremain; i++)//校验数据
{
if(mem_pool[secoff+i]!=0XFF)break;//需要擦除
}
if(i<secremain)//需要擦除
{
w25qxx_erase_sector(secpos*4096); //擦除这个扇区
for(i=0;i<secremain;i++) //复制原来的数据
{
mem_pool[i+secoff]=buf[i];
}
w25qxx_write_no_check(secpos*4096, mem_pool,4096); //写入整个扇区
}else
{
W25QXX_TRACE("no need to erase -addr:%d\r\n", addr);
w25qxx_write_no_check(addr, buf, secremain);//写已经擦除了的,直接写入扇区剩余区间.
}
if(len == secremain)break;//写入结束了
else//写入未结束
{
secpos++;//扇区地址增1
secoff=0;//偏移位置为0
buf += secremain; //指针偏移
addr += secremain;//写地址偏移
len -= secremain; //字节数递减
if(len > 4096) secremain = 4096; //下一个扇区还是写不完
else secremain = len; //下一个扇区可以写完了
}
}
return SPI_EOK;
}
