Rockwell Automation 1747-PCIS API Software - Open Controller - Manual (Page 81)

Publication 1747-UM002A-US-P - June 2000
Library of Routines 6-21
Considerations:
Supported in the DOS API library and the Windows NT API library
Example:
HANDLE Handle;
BYTE count;
int retcode;
retcode = OC_GetInputImageUpdateCounter( Handle, &count );
OC_GetIOConfiguration OC_GetIOConfiguration queries the I/O rack about the installed rack
sizes and I/O modules in each 1746 chassis.
Syntax:
int OC_GetIOConfiguration(HANDLE handle, OCIOCFG
*iocfg);
Parameters:
Description:
If the scanner is in Scan mode and OC_GetIOConfiguration returns
successfully, OC_GetIOConfiguration enables the host application to
access I/O. The scanner must have previously received a valid
configuration prior to going to Scan mode.
The OCIOCFG structure is defined as:
typedef struct tagOCIOCFG
{
BYTE Rack1Size;/* number of slots in Rack 1 */
BYTE Rack2Size;/* number of slots in Rack 2 */
ATTENTION
!
OC_GetIOConfiguration can take several
milliseconds to complete, depending upon the rack
configuration. While it is executing, I/O scanning
and DII’s are disabled.
Parameter: Description:
handle Must be a valid handle returned from OC_OpenScanner
iocfg Specifies the rack sizes and installed modules
Use the information in
iocfg as input to
OC_DownloadIOConfiguration to configure the scanner.