at45d041a读写程序模块.asm

at45d041a读写程序模块

              clr sck
              clr cs
              nop
              nop
              nop
              mov a,#0d2h              ;送读flashrom指令
              acall sent_one_byte
              acall adjust_addr
              mov a,pagehigh
              acall sent_one_byte
              mov a,pagelow
              acall sent_one_byte
              mov a, byte_add_low
              acall sent_one_byte
              acall sent_one_byte      ;sent don't care bit
              acall sent_one_byte
              acall sent_one_byte
              acall sent_one_byte
              nop
              nop
              nop
              mov r2,read_data_len
              mov r0,#read_data_addr
main_pag_lop: acall read_one_byte
              mov @r0,a
              inc r0
              djnz r2,main_pag_lop
              setb cs
              ret
;-----------------------------------------------------
; name:   main_to_buffer
; funct:  把页主存中的数据读到buffer1 or buffer2中
; calls:  sent_one_byte
; InPare: pagehigh, pagelow , buf_choice
; OutPare:
; register usage:  r1,A,C
;----------------------------------------------------
main_to_buffer:
              acall read_status       ;读取busy,
              mov a,status
              rlc a
              jnc main_to_buffer
              clr sck
              clr cs
              nop
              nop
              nop
              mov a,#53h              ;选择buffer1
              jnb buf_choice,main_buf_lop
              mov a,#85h              ;选择buffer2
main_buf_lop: acall sent_one_byte
              acall adjust_addr
              mov a,pagehigh
              acall sent_one_byte
              mov a,pagelow
              acall sent_one_byte
              acall sent_one_byte       ;don't care
              setb cs
              ret
;-----------------------------------------------------
; name:   buffer_read
; funct:  把buffer1 or buffer2中的数据读到MCU
; calls:  sent_one_byte,read_one_byte
; InPare: buf_choice, read_data_len, read_data_addr
;         byte_add_high , byte_add_low
; OutPare: none
; register usage:  r1,A,C
;----------------------------------------------------
buffer_read:
              acall read_status       ;读取busy,
              mov a,status
              rlc a
              jnc main_to_buffer
              clr sck
              clr cs
              nop
              nop
              nop
              mov a,#0d4h              ;选择buffer1
              jnb buf_choice,buffer_rd
              mov a,#0d6h              ;选择buffer2
buffer_rd:    acall sent_one_byte
              acall adjust_addr
              acall sent_one_byte
              mov a,byte_add_high
              acall sent_one_byte
              mov a,byte_add_low
              acall sent_one_byte
              acall sent_one_byte

              mov r2,read_data_len
              mov r0,#read_data_addr
buffer_rd_lop:
              acall read_one_byte
              mov @r0,a
              inc r0
              djnz r2,buffer_rd_lop
              setb cs
              ret
;-----------------------------------------------------
; name:   page_erase
; funct:  擦除一页
; calls:  sent_one_byte,adjust_addr
; InPare: pagehigh, pagelow
; OutPare:
; register usage:  r1,A,C
;----------------------------------------------------
page_erase:
              acall read_status       ;读取busy,
              mov a,status
              rlc a
              jnc page_erase
              clr sck
              clr cs
              nop
              nop
              nop
              mov a,#81h
              acall sent_one_byte
              acall adjust_addr
              mov a,pagehigh
              acall sent_one_byte
              mov a,pagelow
              acall sent_one_byte
              acall sent_one_byte
              setb cs
              ret
;-----------------------------------------------------
; name:   block_erase
; funct:  擦除一块
; calls:  sent_one_byte
; InPare: block_addr
; OutPare: none
; register usage:  r1,r2,A,C
;----------------------------------------------------
block_erase:
              call read_status       ;读取busy,
              mov a,status
              rlc a
              jnc block_erase
              clr sck
              clr cs
              nop
              nop
              nop
              mov a,block_addr       ;调整块地址
              swap a
              mov r2,a
              anl a,#0f0h
              mov block_addr,a
              mov a,r2
              anl a,#0fh
              mov r2,a
              mov a,#50h             ;发送擦除块命令
              acall sent_one_byte
              mov a,r2               ;发送擦除块高位地址
              acall sent_one_byte
              mov a,block_addr       ;发送擦除块低位地址
              acall sent_one_byte
              acall sent_one_byte
              ret
;-----------------------------------------------------
; name:   read_status
; funct:  把flashrom 中status register
; calls:  sent_one_byte , read_one_byte
; InPare: none
; OutPare: status
; register usage:  r1,A,C
;----------------------------------------------------
read_status:
             clr sck
             clr cs
             nop
             nop
             mov a,#0d7h
             acall sent_one_byte
             acall read_one_byte
             mov status,a
             setb cs
             ret
;-----------------------------------------------------
; name:   compare
; funct:  把flashrom 中的指定页数据与buffer1 or buffer2作比较
; calls:  sent_one_byte , read_one_byte
; InPare: buf_choice
; OutPare: data_fault
; register usage:  r0,r1,r2,A,C
;----------------------------------------------------
compare:
             clr sck
             clr cs
             nop
             nop
             nop
             mov a,#60h
             jnb buf_choice,comp
             mov a,#61h
comp:        acall sent_one_byte
             mov a,pagehigh
             acall sent_one_byte
             mov a,pagelow
             acall sent_one_byte
             nop
             nop
             acall sent_one_byte
             setb cs
comp_lop:    acall read_status
             mov a,status
             rlc a
             jnc comp_lop
             rlc a
             jnc comp_ret
             setb data_fault
comp_ret:    ret
;-----------------------------------------------------
; name:   adjust_addr
; funct:  调整页地址、页内字节地址、buffer地址
; calls:  none
; InPare: pagehigh, pagelow, byte_add_high, byte_add_low
; OutPare: pagehigh, pagelow, byte_add_high, byte_add_low
; register usage:  A,C
;----------------------------------------------------
adjust_addr:
            clr c
            mov a,pagelow
            rlc a
            mov pagelow,a
            mov a,pagehigh
            rlc a
            mov pagehigh,a
            mov a,pagelow
            orl a,byte_add_high
            mov pagelow,a
            mov byte_add_high,a
            ret


         end