Intel Flash芯片 i28f160,i28f320:
i28F320B: 64*64K,64个blocks,4M空间,每个block 64K,第一个64K由8个8*8K小blocks组成.每个Black可以被独立擦写(寿命周期) 100,000次以上
Flash操作的大概步骤:
flash读写操作中,读应该很简单,和RAM一样,写就复杂一点.
Intel TE28F320C3的flash是4M空间
flash空间,划分成许多的block,Intel TE28F320C3的flash是4M空间,64个block,每个block由64K.
要对所有的block单独进行操作, 每个操作结束,都需要判断状态,
每个block操作的大概步骤如下:
1.unlock
2.erase
3.check empty
所有的block完成上述操作,且状态正确,才能进行下一步,写
4.write
ARM汇编程序
LDR r2, =FlashBase ;Flash起始地址
//第一步,UNLOCK的64个block,步骤和上边一样
- MOV r1,#63 ;63x64k block 计数
- 01 LDRB r3, =X16_FLASH_COMMAND_CONFIG_SETUP
- STRB r3, [r2] ;该block的首地址
- LDRB r3, =X16_FLASH_COMMAND_UNLOCK_BLOCK
- STRB r3, [r2] ;将Unlock命令写入
- ADD r2, r2, #0x10000 ;64K
- SUBS r1, r1, #1
- BNE %b01
- ;Unlock OK ;Unlock 完成
//第二布,擦除blocks
- LDR r0, =FlashBase
- LDR r1,=63 ;擦除 63x64k block
- 01 LDR r3, =X16_FLASH_COMMAND_ERASE
- LDR r2, =X16_FLASH_COMMAND_CONFIRM
- ORR r3, r3, r2, LSL #16
- STR r3, [r0]
- LDR r3, =X16_FLASH_COMMAND_STATUS ;检查寄存器状态
- STRB r3, [r0]
- 02 LDRB r3, [r0] ;读状态
- TST r3, #X16_FLASH_STATUS_READY
- BEQ %b02 ;若状态ready,执行下一个
- TST r3, #X16_FLASH_STATUS_ERROR
- BNE error_erase_block
- ADD r0, r0, #0x10000
- SUBS r1, r1, #1
- BNE %b01
- B EraseOK
- error_erase_block
- ..............
- ;EraseOK ;擦除完成
//第三步,检查flash是否为空
- ;Check Flash Empty
- LDR r4, =FlashBase
- LDR r5, =0x100000 ;检查 1MB
- LDR r0, =0xffffffff
- loop_1
- LDR r1, [r4]
- CMP r1, r0 ;比较地址内容和0xffffffff
- BNE empty_error
- ADD r4, r4, #4
- CMP r4, r5
- BLO loop_1
- B CheckOK
- empty_error
- .................
- CheckOK
- .................
- ;Check empty OK ;检查完成
//第四步,写flash
- ;Burn data to Flash ROM
- LDR r6, =Length_Flash ;定义数据长度
- LDR r0, =FlashBase
- LDR r1, =BufferBase
- MOV r9, #0
- LDR r4,=0x10000000
- LDR r7,=0xc0001000
- STR r4, [r7]
- LDR r1, [r1, r9]
- 03 LDR r3, =X16_FLASH_COMMAND_WRITE
- STRB r3, [r0] ;把写命令放入Block首地址
- LDR r3, =X16_FLASH_COMMAND_STATUS
- LDR r2, [r7]
- LDR r5, =0x0000ffff
- AND r2, r2, r5
- ORR r2, r2, r3, LSL #16
- STR r2, [r0]
- 02 LDR r3, [r0] ;读状态寄存器状态
- TST r3, #X16_FLASH_STATUS_READY
- BEQ %b02 ;若状态ready,执行下一个
- LDR r3, =X16_FLASH_COMMAND_WRITE
- LDR r2, [r7]
- LDR r5, =0xffff0000 ;
- AND r2, r2, r5
- ORR r3, r3, r2
- STR r3, [r0]
- LDR r3, =X16_FLASH_COMMAND_STATUS
- STRB r3, [r0]
- 02 LDR r3, [r0] ; read status
- TST r3, #X16_FLASH_STATUS_READY
- BEQ %b02
- LDR r4, =X16_FLASH_COMMAND_READ
- STRB r4, [r0]
- ADD r0, r0, #4
- LDR r8, [r7]
- ADD r8, r8,#1
- STR r8, [r7]
- ADD r8, r8, #4
- writenext
- SUBS r6, r6, #4 ;if no finished goto 03
- BHI %b03
- TST r3, #X16_FLASH_STATUS_ERROR
- BNE error_write
- LDR r3, =X16_FLASH_COMMAND_READ
- STRB r3, [r0]
- B BurnOK
- error_write
- ..........
- BurnOK
