Register 1#

Register 2#

Details#

BUSY：忙位（只读），0 表示空闲，1 表示正忙。

WEL：写保护位（只读），执行 Write Enable（06h）指令后 WEL 置 1，写禁用时的 WEL 为 0。

BP2, BP1, BP0：块保护位，默认设置均为 0，不包含任何块。

TB：顶部/底部保护位（非易失读写），控制 BP2/1/0 的保护对象是从顶部（TB=0）还是底部（TB=1）开始，出厂默认设置为 TB=0。

SEC：扇区保护位（非易失读写），控制 TB 和 BP2/1/0 的保护对象是 4KB 扇区（SEC=1）还是 64KB 块（SEC=0），出厂默认设置为 SEC=0。

SRP1, SRP0：状态寄存器保护位（非易失读写），控制写保护方法：

Notes:

1. These features are available upon special order. Please refer to Ordering Information.
2. When SRP1, SRP0 = (1, 0), a power-down, power-up cycle will change SRP1, SRP0 to (0, 0) state.

SUS：挂起状态位（只读），执行 Erase Suspend（75h）后 SUS=0。

QE：四通道使能位（非易失读写），QE=0（出厂默认设置）使能 /WP 和 /HOLD，QE=1 使能 IO2 和 IO3。

Instruction Set Table 1#

(Erase, Program Instructions) ⁽¹⁾

Notes:

1. Data bytes are shifted with Most Significant Bit first. Byte fields with data in parenthesis “()” indicate data being read from the device on the DO pin.
2. The Status Register contents will repeat continuously until /CS terminates the instruction.
3. Quad Page Program Input Data:
   • IO0 = (D4, D0, ……)
   • IO1 = (D5, D1, ……)
   • IO2 = (D6, D2, ……)
   • IO3 = (D7, D3, ……)
4. This instruction is recommended when using the Dual or Quad “Continuous Read Mode” feature. See section 11.2.32 for more information.

Instruction Set Table 2#

Read Instructions

Notes:

1. Dual Output data
   • IO0 = (D6, D4, D2, D0)
   • IO1 = (D7, D5, D3, D1)
2. Dual Input Address
   • IO0 = A22, A20, A18, A16, A14, A12, A10, A8 A6, A4, A2, A0, M6, M4, M2, M0
   • IO1 = A23, A21, A19, A17, A15, A13, A11, A9 A7, A5, A3, A1, M7, M5, M3, M1
3. Quad Output Data
   • IO0 = (D4, D0, …..)
   • IO1 = (D5, D1, …..)
   • IO2 = (D6, D2, …..)
   • IO3 = (D7, D3, …..)
4. Quad Input Address
   • IO0 = A20, A16, A12, A8, A4, A0, M4, M0
   • IO1 = A21, A17, A13, A9, A5, A1, M5, M1
   • IO2 = A22, A18, A14, A10, A6, A2, M6, M2
   • IO3 = A23, A19, A15, A11, A7, A3, M7, M3
5. Fast Read Quad I/O Data
   • IO0 = (x, x, x, x, D4, D0, …..)
   • IO1 = (x, x, x, x, D5, D1, …..)
   • IO2 = (x, x, x, x, D6, D2, …..)
   • IO3 = (x, x, x, x, D7, D3, …..)
6. Word Read Quad I/O Data
   • IO0 = (x, x, D4, D0, …..)
   • IO1 = (x, x, D5, D1, …..)
   • IO2 = (x, x, D6, D2, …..)
   • IO3 = (x, x, D7, D3, …..)
7. The lowest address bit must be 0. ( A0 = 0 )
8. The lowest 4 address bits must be 0. ( A0, A1, A2, A3 = 0 )

Instruction Set Table 3#

ID, Security Instructions

Notes:

1. The Device ID will repeat continuously until /CS terminates the instruction.
2. See Manufacturer and Device Identification table for Device ID information.

FLASH 状态确认/设备测试#

在初始化阶段判断 FLASH 状态的常用方法有两种，分别是 JEDEC ID 和 S0-BUSY。

JEDEC ID

W25Q16 的 JEDEC ID 由3个字节组成，分别是：

• Manufacturer ID (0xEF)
• Memory Type
• Capacity

以我 W25Q16JVSSIQ 为例，发送 0x9F 后，读取3个字节（0xEF : 0x40 : 0x15）。

1
unsigned char SPI_FLASH_CheckStatus(void)
2
{
3
    unsigned char b1, b2, b3;
4
    unsigned char i = 0;
5
    while (i++ < 200)
6
    {
7
        SPI_FLASH_CS=0;
8
        SPI_WriteByte(W25X_ReadJEDECID);
9
        b1 = SPI_ReadByte();
10
        b2 = SPI_ReadByte();
11
        b3 = SPI_ReadByte();
12
        SPI_FLASH_CS=1;
13
        if (b1 == 0xEF & b2 == 0x40 & b3 == 0x15) return 1;
14
        delayms(1);
15
    }
16
    return  0;
17
}

S0-BUSY

1
unsigned char SPI_FLASH_CheckStatus(void)
2
{
3
    unsigned char b1;
4
    unsigned char i = 0;
5
    while(i++ < 200)
6
    {
7
        SPI_FLASH_CS=0;
8
        SPI_WriteByte(W25X_ReadStatus1);
9
        b1 = SPI_ReadByte();
10
        SPI_FLASH_CS=1;
11
        if (!(b1 & 0x01)) return 1;
12
        delayms(1);
13
    }
14
    return 0;
15
}