Add support for non standard feature: allow POUs with no in, out and inout parameters
FUNCTION_BLOCK FWD_REV_MON
VAR_INPUT AUTO : BOOL ;(* Enable automated commands *)
ACK : BOOL ; (* Acknowledge/cancel all alarms *)
AUTO_FWD : BOOL ; (* Automated forward command *)
MAN_FWD : BOOL ; (* Manual forward command *)
MAN_FWD_CHK : BOOL ; (* Negated MAN_FWD for debouncing *)
T_FWD_MAX : TIME ; (* Maximum time from FWD_CMD to FWD_FDBK *)
FWD_FDBK : BOOL ; (* Confirmation of FWD_CMD completion *)
(* by operative unit *)
AUTO_REV : BOOL ; (* Automated reverse command *)
MAN_REV : BOOL ; (* Manual reverse command *)
MAN_REV_CHK : BOOL ; (* Negated MAN_REV for debouncing *)
T_REV_MAX : TIME ; (* Maximum time from REV_CMD to REV_FDBK *)
REV_FDBK : BOOL ; (* Confirmation of REV_CMD completion *)
END_VAR (* by operative unit *)
VAR_OUTPUT KLAXON : BOOL ; (* Any alarm active *)
FWD_REV_ALRM : BOOL; (* Forward/reverse command conflict *)
FWD_CMD : BOOL ; (* "Forward" command to operative unit *)
FWD_ALRM : BOOL ; (* T_FWD_MAX expired without FWD_FDBK *)
REV_CMD : BOOL ; (* "Reverse" command to operative unit *)
REV_ALRM : BOOL ; (* T_REV_MAX expired without REV_FDBK *)
END_VAR
VAR FWD_MON : CMD_MONITOR; (* "Forward" command monitor *)
REV_MON : CMD_MONITOR; (* "Reverse" command monitor *)
FWD_REV_FF : SR ; (* Forward/Reverse contention latch *)
END_VAR
(* Function Block body *)
LD AUTO (* Load common inputs *)
ST FWD_MON.AUTO_MODE
ST REV_MON.AUTO_MODE
LD ACK
ST FWD_MON.ACK
ST REV_MON.ACK
ST FWD_REV_FF.R
LD AUTO_FWD (* Load inputs to FWD_MON *)
ST FWD_MON.AUTO_CMD
LD MAN_FWD
ST FWD_MON.MAN_CMD
LD MAN_FWD_CHK
ST FWD_MON.MAN_CMD_CHK
LD T_FWD_MAX
ST FWD_MON.T_CMD_MAX
LD FWD_FDBK
ST FWD_MON.FDBK
CAL FWD_MON (* Activate FWD_MON *)
LD AUTO_REV (* Load inputs to REV_MON *)
ST REV_MON.AUTO_CMD
LD MAN_REV
ST REV_MON.MAN_CMD
LD MAN_REV_CHK
ST REV_MON.MAN_CMD_CHK
LD T_REV_MAX
ST REV_MON.T_CMD_MAX
LD REV_FDBK
ST REV_MON.FDBK
CAL REV_MON (* Activate REV_MON *)
LD FWD_MON.CMD (* Check for contention *)
AND REV_MON.CMD
S1 FWD_REV_FF (* Latch contention condition *)
LD FWD_REV_FF.Q
ST FWD_REV_ALRM (* Contention alarm *)
LD FWD_MON.CMD (* "Forward" command and alarm *)
ANDN FWD_REV_ALRM
ST FWD_CMD
LD FWD_MON.ALRM
ST FWD_ALRM
LD REV_MON.CMD (* "Reverse" command and alarm *)
ANDN FWD_REV_ALRM
ST REV_CMD
LD REV_MON.ALRM
ST REV_ALRM
OR FWD_ALRM (* OR all alarms *)
OR FWD_REV_ALRM
ST KLAXON
END_FUNCTION_BLOCK