Category:Flash

Knowlege

• 绝大多数的单片机和微控制器（ARM,x86)，地址空间都是以字节为单位的，也就是说一个地址是一个字节。
• Flash存储器有个特点，就是只能写0，不能写1。所以如果原来的地址有数据了，意味着有一些位为0，这些位就相当于无效了。所以必须写之前确保他们都为1，只有擦除才可以。另外每次擦除都必须擦除一个4K大小的扇区，这是flash的特性所决定的。
• 对Flash操作前必需打开内部振荡器。

STM32 Code

Read, notice address should be 0x08006900 ... 0x08006910 ... 0x08006920

uint8_t dat1 = *(__IO uint32_t *)(0x08006900);
uint8_t dat2 = *(__IO uint32_t *)(0x08006910);
uint8_t dat3 = *(__IO uint32_t *)(0x08006920);

• 

  address map of STM32F030

SPI Flash

• SST - SST25VF016B-50-4C-S2AF
• Winbond - W25Q64FVSSIG

• Simple wiring

D13, D12, D11, D10 of arduino to SPI flash - CLK, DO, DI and CS, 
3V3 arduino to 3v3, wp, hold, and GND of arduino to GND

• Data need to be erased before write again.
• flash winbond W25Q SPI Flash

• Arduino SPIFlash library

Programming

Programming by CH341

• Use tool CH341 Programmer from github, download below
• wiring please refer to page Flash#Pin_Wiring, use CE0 for this board
• Switch board power supply to 3V3, and MODE to others
• press "detect" in tools and you should see like this.

(Obsolete) Update on-board SPI-Flash

Here is an example of our MT7688AN board, flash uboot or firmware

• 

  01 wire up

• 

  02 connect to programmer

• 

  Click program to upload

• No need to connect anymore, use programmer power supply
• Connect pin VDD, MOSI, CLK, MISO, CS, GND
• Detect on board SPI Flash size 16Mb, which is W25Q128FVSSIG
• Upload you file, uboot or firmware