Format  Sint32 CDC_CalActSiz (Sint32 bufno, Sint32 spos, Sint32 snum)
 Input  bufno: Buffer partition number
:  spos: Sector position (CDC_SPOS_END: ​​Indicates the last sector of the section)
  snum: Number of sectors (CDC_SNUM_END: ​​Indicates the number of sectors from spos to the end of the partition)
 Output  None
 Function value  Returns an error code.
 End flag  ESEL flag
 Function  From the specified sector range of the buffer partition, the actual data size (number of words when fetching to the host)
 Calculates . To obtain the calculation result, execute Get actual data size (CDC_GetActSiz).
In case of  error , the actual data size is as follows. 

constant name	description
CDC_ACTSIZ_ERR	Calculation could not be performed.

: The length of one sector can be changed by setting the sector length (CDC_SetSctLen).
Remarks Connectors already connected to the partition output connector will be disconnected.

 format  Sint32 CDC_GetActSiz (Sint32 * actwnum)
 Input  None
 Output  actwnum: Actual data size (number of words)
 Function value  Returns an error code.
 End flag  ESEL flag (only checked)
 Function  Obtains the actual data size calculation result (initial value 0).
  The previous calculation result is retained until the next calculation (CDC_CalActSiz) is executed. 

 format  Sint32 CDC_GetSctInfo (Sint32 bufno, Sint32 spos, CdcSct * sct)
 Input  bufno: Buffer partition number
:  spos: Sector position (CDC_SPOS_END: ​​Indicates the last sector of the section)
 Output  sct: Sector information
 Function value  Returns an error code.
 Function  Gets header information (FAD) and subheader information for the specified sector in the buffer section.