Rockwell Automation 1747-PCINT API Software for 1746 I/O - Manual (Page 89)

OC_GetScanner WatchdogCount Library of Routines 6–35
Publication 1747-6.5.3 June 1998
OC_GetScanner
WatchdogCount OC_GetScannerWatchdogCount reads the contents of the watchdog register of the
scanner.
Syntax:
int OC_GetScannerWatchdogCount(HANDLE handle, BYTE *count);
Parameters:
Description:
The watchdog register is incremented by the scanner after every timed I/O scan.
This register is incremented in both Scan and Idle modes, and is incremented even if both output and input
scans are disabled. The control application can monitor this register to ensure that the scanner is functioning
normally. It is also useful for synchronizing with the I/O scan.
Return Value:
Considerations:
Supported in the DOS API library and the Windows NT API library
Example:
HANDLE Handle;
BYTE wdog_count;
int retcode;
retcode = OC_GetScannerWatchdogCount( Handle, &wdog_count );
Parameter: Description:
handle Must be a valid handle returned from OC_OpenScanner
count Returns the watchdog register contents
Name: Value: Description:
SUCCESS 0 watchdog was read successfully
ERR_OCACCESS
2
handle does not have access to scanner