Rockwell Automation 1747-PCINT API Software for 1746 I/O - Manual (Page 118)

6–64 Library of Routines OC_SetForces
Publication 1747-6.5.3 June 1998
OC_SetForces OC_SetForces installs and removes input and output forces to the scanner.
Syntax:
int OC_SetForces(HANDLE handle, FORCEDATA *forcedata)
Parameters:
Description:
If the result of OC_SetForces removes all I/O forces, the scanner disables forces. If any I/O forces are later
installed, OC_EnableForces must be called to re-enable forces.
The FORCEDATA structure is defined as:
typedef struct tagFORCEDATA {
BYTE SlotNum; /* Slot Number of local I/O or 1747-SN module (1-30)*/
WORD WordOffset; /* Word Offset in I/O image */
BYTE IOType; /* Selects Input or Output Image */
WORD ForceMask; /* Install/Remove bitmask */
WORD ForceVal; /* Install value bitmask */
} FORCEDATA;
Parameter: Description:
handle Must be a valid handle returned from OC_OpenScanner
forcedata Defines the inputs and outputs to force.
This value: Means:
SlotNum
WordOffset
SlotNum and WordOffset select the word of I/O that contains the bits
to be forced
IOType IOType must be FORCE_INPUTS or FORCE_OUTPUTS
ForceMask
ForceVal
All 16 bits of the word are installed/removed according to ForceMask
and ForceVal
Each bit in ForceMask that is set to 0 will have its force removed. Each
bit in ForceMask that is set to 1 will have its force installed. For each bit
that has its force installed, the corresponding bit in ForceVal determines
the state of the force. For bits that have their force removed, the
corresponding bit in
ForceVal is ignored.