PRODAVE软件包中包含有函数的说明和使用示例我看了，但是我觉得好像是对300与400操作的。比如
Declare Function db_read Lib "w95_s7.dll" (ByVal db As Long, ByVal dw As Long, anz As Long, value As Integer) As Long
Declare Function db_write Lib "w95_s7.dll" (ByVal db As Long, ByVal dw As Long, anz As Long, value As Integer) As Long

Declare Function d_field_read Lib "w95_s7.dll" (ByVal db As Long, ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
Declare Function d_field_write Lib "w95_s7.dll" (ByVal db As Long, ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
' DATANO, amount, value
Declare Function e_field_read Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
Declare Function a_field_read Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
Declare Function a_field_write Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
Declare Function m_field_read Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
Declare Function m_field_write Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Byte) As Long
Declare Function t_field_read Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Integer) As Long
Declare Function z_field_read Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Integer) As Long
Declare Function z_field_write Lib "w95_s7.dll" (ByVal nr As Long, ByVal anz As Long, value As Integer) As Long

好像是对数据块等操作的。可是对200如何操作呢？比如V区　M区等