Do_clearbits, Syntax, Remarks – Rockwell Automation 6182 SDK User Manual
Page 45: Return value, Portability, See also
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RAC6182-Specific Extensions to the CE API
4–5
Publication 6182-UM002B-EN-P
do_ClearBits
This function clears digital outputs. It is prototyped in
DiagnosticOutputAPI.h.
Syntax
#include
#include
BOOL do_ClearBits(UCHAR ucMask)
Remarks
This function clears any output whose corresponding bit in ucMask is 1
to a logic FALSE. For the relay output, FALSE is equivalent to open;
for TTL outputs, it is equivalent to a low level. All outputs whose bits in
ucMask are 0 are left unchanged.
Note that the relay contacts are normally closed (i.e., closed when the
relay is not energized). Thus, when the relay output is set to 1 or TRUE,
the contacts will be open and vice versa.
The following macros may be used (separately or bitwise ORed together)
to evaluate ucMask:
Macro
Digital Output
MASK_DIAG_PIN_A
J10, pin A (no external access)
MASK_DIAG_PIN_B
J10, pin B (no external access)
MASK_DIAG_PIN_C
J10, pin C (no external access)
MASK_DIAG_PIN_D
J10, pin D (no external access)
MASK_RELAY_PIN
J16 (Relay – contacts NC)
Return Value
TRUE if read operation was successful, else FALSE.
Portability
This function is specific to the RAC6182 hardware.
See Also
do_SetBits, do_ToggleBits, do_WritePort