7113.asm

51控制SAA7113的初始化程序 ASM格式

SDA              BIT   P1.0
SCL              BIT   P1.1
I2C_ERROR        BIT   00H    ；I2C总线数据传输出错标志
DeviceaddressW   EQU   4AH    ；7113器件地址+写
DeviceaddressR   EQU   4BH    ；7113器件地址+读
Subaddress       EQU   4DH    ；7113寄存器地址字节在单片机中的存放地址
DATA_I2C         EQU   50H    ；设置写入或读出数据在单片机中的存放地址

；*************启动**************
I2C_START:    SETB   SDA
               NOP
               SETB   SCL
               NOP
               CLR    SDA
               NOP
               CLR    SCL
               RET
;***************停止**************
I2C_STOP:     CLR    SDA
               NOP
               SETB   SCL
               NOP
               SETB   SDA
               NOP
               RET
;************送应答位************
SEND_ACK:    CLR    SCL
               NOP
               CLR    SDA
               NOP
               SETB   SCL
               NOP
               NOP
               CLR    SCL
               NOP 
               SETB   SDA
               RET
;***********送非应答位***********
SEND_NOACK: SETB   SDA
              NOP
              SETB   SCL
              NOP
              NOP
              CLR    SCL
              NOP
              RET
;***********检查应答位************
CHECK_ACK:  NOP
              CLR    SCL
              NOP
              SETB   SDA
              NOP
              SETB   SCL
              NOP
              NOP
              MOV   C, SDA
              MOV   I2C_ERROR, C
              CLR    SCL
              NOP
              RET
;*******发送1字节数据，待送数据在A中******
I2C_SEND_1BYTE:
              MOV   R0,  #8
   SEND100:  RLC    A
              MOV   SDA,  C
              NOP
              SETB   SCL
              NOP
              NOP
              CLR    SCL
              DJNZ   R0, SEND100
              RET
;*******接收1字节数据，接收数据放在A中*****
I2C_RECEIVE_1BYTE:
              MOV   R0,  #8
  RECV100:   SETB   SDA
              NOP
              SETB   SCL
              NOP
              NOP
              NOP
              MOV   C,  SDA
              CLR    SCL
              RLC    A
              DJNZ   R0,  RECV100
              RET
；*******通过I2C总线向某一寄存器写入一个字节数据*********
I2C_WRITE:   ACALL  I2C_START          ；发启动信号
              MOV    A， # DeviceaddressW ；调7113地址+写
              ACALL  I2C_SEND_1BYTE    ；发送7113地址及“写”命令
              ACALL  CHECK_ACK         ；检查7113的应答信号
              JNB     I2C_ERROR, WR200   ；应答正确，继续
WR100:     ACALL  I2C_STOP            ；应答不对，返回
              RET
WR200:     MOV    A,  Subaddress        ；调寄存器地址
            ACALL  I2C_SEND_1BYTE    ；发送寄存器地址
              ACALL  CHECK_ACK         ；检查7113的应答信号
            JB       I2C_ERROR, WR100   ；应答不对，返回
            MOV    A,  DATA_I2C        ；调准备写入的数据
            ACALL  I2C_SEND_1BYTE     ；发送数据字节
              ACALL  CHECK_ACK
            JB       I2C_ERROR, WR100
            ACALL  I2C_STOP             ；发停止信号
            RET
；*******通过I2C总线读出某一寄存器的数据*********
I2C_READ:    ACALL  I2C_START
              MOV    A, # DeviceaddressW   ；调7113地址，写入
              ACALL  I2C_SEND_1BYTE
              ACALL  CHECK_ACK
              JNB     I2C_ERROR, RD200
RD100:    ACALL  I2C_STOP
          RET
RD200:    MOV   A, Subaddress          ；调要读的寄存器地址
              ACALL  I2C_SEND_1BYTE     ; 发送寄存器地址字节
              ACALL  CHECK_ACK
          JB       I2C_ERROR, RD100
          ACALL  I2C_START           ；重发起动信号
          MOV    A, # DeviceaddressR    ；调7113地址，读
              ACALL  I2C_SEND_1BYTE
              ACALL  CHECK_ACK
          JB       I2C_ERROR, RD100
          ACALL  I2C_RECEIVE_1BYTE  ；接收读出的数据
          MOV    DATA_I2C,  A         ；读出数据转存
          ACALL  SEND_NOACK         ；发送非应答位
          ACALL  I2C_STOP              ；停止
          RET
；***************初始化7113，配置各寄存器************************
 INIT_SAA7113:    MOV DPTR, #SAA7113_Subaddress
               MOV R7, #28
INIT100:       MOV A, #0
               MOVC  A, @A+DPTR
               MOV Subaddress,  A     ；调寄存器地址
               MOV A,#28
               MOVC  A, @A+DPTR
               MOV DATA_I2C, A       ；调寄存器配置数据
               INC  DPTR
               ACALL I2C_WRITE     ；配置1个寄存器
               JB I2C_ERROR, INIT200
               DJNZ R7,INIT100
INIT200:      RET
；***************SAA7113寄存器初始化配置数据**********************
SAA7113_Subaddress:
 DB 01H,02H,03H,04H,05H,06H,07H,08H,09H,0AH,0BH,0CH,0DH,0EH
 DB 0FH,10H,11H,12H,13H,15H,16H,17H,40H,58H,59H,5AH,5BH,5EH
    ；共28个
I2C_REG_VALUE_AI11:
 DB 08H,0C0H,33H,00H,00H,0EBH,0E0H,0B8H,01H,7EH,46H,43H,01H,01H
 DB 0FH,00H,0CH,0A7H,00H,00H,00H,00H,02H,00H,54H,07H,80H,00H
；*************对SAA7113某一寄存器的改写与读出*******************
WRITE_READ:     MOV  Subaddress, #0AH   ; 设寄存器地址为0AH
                  MOV  DATA_I2C, #88H    ；改寄存器的值为88H
                  ACALL I2C_WRITE     ；改写
               ACALL I2C_READ      ；读出