PLCnext Technology System Variables

System variable			Type	Description
DEVICE_STATE			DEVICE_STATE_X152_TYPE	Data structure
1	BOARD_TEMPERATURE		SINT	Temperature inside the housing (in °C).
1	reserved1		BOOL	Reserved
1	RAMDISK_USAGE		USINT	Current usage of the RAM memory.
1	CPU_LOAD_ALL_CORES		USINT	Average current utilization of all processor cores (in %).
1	CPU_LOAD_PER_CORE		CPU_LOAD_PER_CORE_ARRAY	Information on the utilization of each processor core.
1	1	[1]	USINT	Current utilization of processor core 1 (in %).
1	1	[2]	USINT	Current utilization of processor core 2 (in %).
1	1	[3]	USINT	Current utilization of processor core 3 (in %).

System variable			Type	Description
RTC			RTC_TYPE	Data structure
1	HOURS		USINT	System time (hours)
1	MINUTES		USINT	System time (minutes)
1	SECONDS		USINT	System time (seconds)
1	DAY		USINT	System time (day)
1	MONTH		USINT	System time (month)
1	YEAR		UINT	System time (year)

System variable			Type	Description
USER_PARTITION			PARTITION_INFO	Data structure
1	MEM_TOTAL		ULINT	Total memory of the partition in bytes (including reserved blocks).
1	MEM_FREE		ULINT	Free, available memory in bytes (without reserved blocks).
1	MEM_USED		ULINT	Used memory in bytes (including reserved blocks).
1	MEM_HANDLING		ULINT	Used memory in % (without reserved blocks).

System variable						Type	Description
ESM_DATA						ESM_DAT	Data structure
1	ESM_COUNT					USINT	Number of ESMs (one ESM per processor core).
1	ESM_INFOS					ESM_INFO_ARRAY	1
1	1	[1] ... [2]				ESM_INFO	Information about the ESM [1 ... 2] 2.
1	1	1	TASK_COUNT			UINT	Number of tasks that were configured for the ESM.
1	1	1	TICK_COUNT			UDINT	Always 0
1	1	1	TASK_INTERVAL			UDINT	Always 0
1	1	1	TASK_INFOS			TASK_INFO_ARRAY	1
1	1	1	1	[1] ... [16]		TASK_INFO	Information about the tasks [1 ... 16].
1	1	1	1	1	INTERVAL 1	LINT	Time interval With cyclic tasks: Time interval in μs With acyclic tasks: 0
1	1	1	1	1	PRIORITY 1	INT	Priority of the task.
1	1	1	1	1	WATCHDOG 1	LINT	Watchdog time in μs (0 = no watchdog). Watchdog time you define for the sum of the execution time and the delay time. If the watchdog time is exceeded, the watchdog is triggered.
1	1	1	1	1	LAST_EXEC_DURATION	LINT	Execution time of the task in the previous cycle in μs. This also includes interruptions due to higher-priority tasks.
1	1	1	1	1	MIN_EXEC_DURATION	LINT	Minimum execution time of the task in μs. This also includes interruptions due to higher-priority tasks.
1	1	1	1	1	MAX_EXEC_DURATION	LINT	Maximum execution time of the task in μs. This also includes interruptions due to higher-priority tasks.
1	1	1	1	1	LAST_ACTIVATION_DELAY	LINT	Delay time of the task in the previous cycle in μs. A delay occurs when higher priority tasks are pending at the time of task activation.
1	1	1	1	1	MIN_ACTIVATION_DELAY	LINT	Minimum delay time of the task in μs. A delay occurs when higher priority tasks are pending at the time of task activation.
1	1	1	1	1	MAX_ACTIVATION_DELAY	LINT	Maximum delay time of the task in μs. A delay occurs when higher priority tasks are pending at the time of task activation.
1	1	1	1	1	EXEC_TIME_THRESHOLD 1	LINT	Threshold that you can define for the sum of the execution time and the delay time.
1	1	1	1	1	EXEC_TIME_THRESHOLD _CNT	ULINT	If the defined threshold EXEC_TIME_THRESHOLD is exceeded, the value of the variable EXEC_TIME_THRESHOLD_CNT is incremented.
1	1	1	1	1	NAME 1	STRING	Name of the task.
1	EXCEPTION_COUNT					USINT	Number of exceptions.
1	EXCEPTION_INFOS					ESM_EXCEPTION_INFO_ARRAY	1
1	1	[1] ... [2]				ESM_EXCEPTION_INFO	Information on the exceptions [1 ... 2] 2.
1	1	1	TYPE_ID			UDINT	ID of the exception.
1	1	1	SUB_TYPE			STRING512	Exception type
1	1	1	SUB_TYPE_ID			UDINT	ID of the task in which the exception occurred.
1	1	1	TASK_NAME			STRING	Name of the task in which the exception occurred.
1	1	1	PROGRAM_NAME			STRING512	Name of the program instance in which the exception occurred.
1	1	1	INFORMATION			STRING512	Information about the exception that occurred.

1  You can set the system variable in the 'Tasks and Events' editor.

2  Some CPUs only support ESM1.

System variable	Type	Description
PND_S1_PLC_RUN	BOOL	TRUE means higher level controller is in RUN mode.
PND_S1_VALID_DATA_CYCLE	BOOL	TRUE if I-Device configuration is ok. To retrieve the value, the controller must be connected but can be in STOP or RUN mode.
PND_S1_OUTPUT_STATUS_GOOD	BOOL	Status of output data. To retrieve the value, the controller must be connected and in RUN mode.
PND_S1_INPUT_STATUS_GOOD	BOOL	Status of input data. To retrieve the value, the controller must be connected and in RUN mode.
PND_S1_DATA_LENGTH	WORD	Length of input and output data in Byte. The value is only updated if the controller is connected and PND_S1_VALID_DATA_CYCLE = TRUE.
PND_S1_OUTPUTS	PND_IO_512	1
PND_S1_INPUTS	PND_IO_512	1
PND_IO_DRIVEN_BY_PLC	INT	Applicative system redundancy number of the Profinet controller currently connected to the PN device. Possible values: 0 = No Profinet controller 1 = Profinet controller A 2 = Profinet controller B The value is only updated if the controller is connected and PND_S1_VALID_DATA_CYCLE = TRUE.

System variable	Type	Description
PNIO_SYSTEM_BF	BOOL	If TRUE, a missing connection to a configured Profinet device has been detected: An error has occurred in the Profinet network, i.e., no connection could be established to at least one configured Profinet device. This value is not set if the Drive BF parameter on a Profinet device was set to FALSE. The Profinet device was thus removed from the connection monitoring.
PNIO_SYSTEM_SF	BOOL	If TRUE, a diagnostic interrupt occured on a configured Profinet device: At least one Profinet device reports a system error as a diagnostic interrupt or maintenance alarm. The error priority can be found in the following variables: PNIO_MAINTENANCE_DEMANDED and PNIO_MAINTENANCE_REQUIRED.
PNIO_MAINTENANCE_DEMANDED	BOOL	If TRUE, a maintenance demand is indicated: At least one Profinet device reports a "maintenance demand". Maintenance alarm with high priority when the connection is active. The affected Profinet device can be identified by means of the RALRM diagnostic function block.
PNIO_MAINTENANCE_REQUIRED	BOOL	If TRUE, a maintenance demand is indicated: At least one Profinet device reports a "maintenance required". Maintenance alarm with low priority when the connection is active. The affected Profinet device can be identified by means of the RALRM diagnostic function block.
PNIO_CONFIG_STATUS	WORD	Configuration status of the Profinet controller. The word value represent the following mapping: Bit 0: PNIO_CONFIG_STATUS_READY Bit 1: PNIO_CONFIG_STATUS_ACTIVE Bit 2: PNIO_CONFIG_STATUS_CFG_FAULT
PNIO_CONFIG_STATUS_ACTIVE	BOOL	Target configuration loaded. TRUE if a target configuration was written to the Profinet controller. In this state, the Profinet controller tries cyclically to establish a connection to all devices of the target configuration.
PNIO_CONFIG_STATUS_READY	BOOL	Profinet controller initialized. TRUE if the Profinet controller could be initialized without errors. FALSE if no target configuration has been written from PLCnext Engineer.
PNIO_CONFIG_STATUS_CFG_FAULT	BOOL	Desired Profinet controller configuration has not been applied due to a serious error.
PNIO_FORCE_FAILSAFE	BOOL	All Profinet devices are prompted to set their configured substitute values. The system variable can be written/set from your application program, if required.
PNIO_FORCE_PRIMARY	BOOL	Function blocks use this variable for applicative redundancy to specify the SRL role of the Profinet controller.

System variable	Type	Description
SPNS	SPNSV2_TYPE	Data structure
PRJ
NAME	STRING	PLCnext Engineer project name.
CRC	DWORD	Project CRC (32 bits) of the Safety PLC boot project.
EXEC_TIME	UDINT	Runtime of the Safety PLC program cycle in µs.
HAS_PRJ	BOOL	The safety-related application program and the program source are available in the memory of the Safety PLC.
DIAG
STATUS_REG	WORD	Diagnostic status register which contains the status information of the Safety PLC. It mirrors the state of the Safety PLC at all times including any error states that have occurred on the Safety PLC. Additional information and error parameters, in particular in the failure state (FS), are included in the relevant diagnostic parameter registers of the Safety PLC (elements SPNS.DIAG.PARAM_REG and SPNS.DIAG.PARAM_2). Details on the information in the diagnostic status register can be found in the Controller Manual.
PARAM_REG	WORD	Diagnostic parameter register 1 of the Safety PLC (error code).
PARAM_2_REG	WORD	Diagnostic parameter register 2 of the Safety PLC (additional error messages for service/support).
EXT_PARAM_REG	DWORD	Extended diagnostic parameter register of the Safety PLC (additional error messages for service/support).
CH2_PARAM_REG	WORD	Diagnostic parameter register 1 of the Safety PLC channel 2 (CH2) (error code).
CH2_PARAM_2_REG	WORD	Diagnostic parameter register 2 of the Safety PLC channel 2 (CH2) (additional error messages for service/support).
CH2_EXT_PARAM_REG	DWORD	Extended diagnostic parameter register of the Safety PLC channel 2 (CH2) (additional error messages for service/support).
INFO
CYCLE_TIME	UDINT	Safety PLC cycle in µs
TEMP
TEMP_CURRENT	INT	Currently measured Safety PLC temperature
TEMP_MIN	INT	Minimum measured Safety PLC temperature since the last power-on of the device.
TEMP_MAX	INT	Maximum measured Safety PLC temperature since the last power-on of the device.
STATUS_REG	WORD	Safety PLC temperature status register 0x0000: The temperature of the Safety PLC is in the non-critical range <= 63 °C. 0x0080: The temperature of the Safety PLC is in the critical range, close to the tolerance threshold >= 64 °C and <= 73 °C. The Safety PLC remains in RUN state and, at the same time, issues a warning with error code 0xFA41. 0x8000: The temperature of the Safety PLC is beyond the permitted range (>= 74 °C). The Safety PLC goes into safe state and issues an error message with error code 0x924D.
CPU
LOAD_CURRENT	INT	Current Safety PLC CPU load
LOAD_MIN	INT	Minimum measured Safety PLC CPU load since the last power-on of the device
LOAD_MAX	INT	Maximum measured Safety PLC CPU load since the last power-on of the device
STATUS_REG	WORD	Safety PLC CPU status register
FW_Version
VERSION_MAJOR	BYTE	Major version of the Safety PLC firmware
VERSION_MINOR	BYTE	Minor version of the Safety PLC firmware
VERSION_BUILD	WORD	Build number of the Safety PLC firmware
FPGA_VERSION
VERSION_MAJOR	BYTE	Major version of the Safety PLC hardware FPGA
VERSION_MINOR	BYTE	Minor version of the Safety PLC hardware FPGA
VERSION_BUILD	WORD	Build number of the Safety PLC hardware FPGA
NUM_OF_ACTIVE_ARS	UINT	Number of active Profinet application relations (AR)
FW_UPDATE_STATUS	UINT	Status of safety-related firmware update
SOFT_RESET_REG	WORD	Software reset register of the Safety PLC

System variable	Type	Description
SPLC_CONTROL_COMMAND	SPNS_CONTROL_TYPE	Data structure with 32 bits for enabling Safety PLC functions.
CODE	DWORD	Bit 0: Resets the minimum and maximum safety roundtrip times (SRT_MIN, SRT_MAX). Data direction: Standard controller > Safety PLC.
PARAM	DWORD	Bits 1 to 31: Reserved.

System variable	Type	Description
SPLC_CONTROL_CONFIRM	SPNS_CONTROL_TYPE	Data structure with 32 bits for confirming functions of the Safety PLC that have been requested via the SPLC_CONTROL_COMMAND variable.
CODE	DWORD	Bit 0: Confirms the resetting of the minimum and maximum safety roundtrip times (SRT_MIN, SRT_MAX). Data direction: Safety PLC > standard controller.
PARAM	DWORD	Bits 1 to 31: Reserved.

System variable	Type	Description
SPLC_CYCLE_TIME	SAFEDINT	Cycle time of the SafetyProxy Task executed by the Safety PLC. The value is read at the beginning of each cycle and is only valid after 16 cycles. It is provided as a moving (smoothed) average value in µs.
SPLC_CYCLE_DURATION	SAFEDINT	Program execution time of the Safety PLC (measured from the activation of the cycle to the end of the cycle). The cycle duration includes the reading of the standard input data, the safety-related input messages, the runtime of the safety-related I/O stacks, the runtime of the safety program, the runtime of the synchronization between both channels, the runtime of all error-controlling measures that are executed in the context of the cycle, and the write operation of the safety-related output data. The value is read at the beginning of each cycle and is only valid after 16 cycles. It is provided as a moving (smoothed) average value in µs.
SPLC_TEMPERATURE	SAFEDINT	Temperature of the Safety PLC. The value is read at the beginning of each cycle. It has the unit °C.
SPLC_PRJ_CRC	SAFEWORD	Project checksum of the safety-related application. The value is read once from the bootproject header.
SPLC_CLOCK_PULSE_1S	SAFEBOOL	Symmetrical clock pulse 1s (High 1s -> Low 1s). Pulse sequence with T/2 = 1 second (T = 2s). For this functionality, the safety-related time base of each channel (resolution 1ms) is used. Each channel has its own safety-related time base, which is synchronized between the channels. From this, each channel forms the pulses independently. The edge changes are cycle-synchronous. The accuracy of the clock pulses (period duration T) depends on the cycle time: Treal = T + ΔT with ΔT <= cycle time
SPLC_CLOCK_PULSE_1M	SAFEBOOL	Symmetrical clock pulse 1m (High 1m -> Low 1m). Pulse sequence with T/2 = 1 minute (T = 2m). For this functionality, the safety-related time base of each channel (resolution 1ms) is used. Each channel has its own safety-related time base, which is synchronized between the channels. From this, each channel forms the pulses independently. The edge changes are cycle-synchronous. The accuracy of the clock pulses (period duration T) depends on the cycle time: Treal = T + ΔT with ΔT <= cycle time
SPLC_CLOCK_PULSE_1H	SAFEBOOL	Symmetrical clock pulse 1h (High 1h -> Low 1h). Pulse sequence with T/2 = 1 hour (T = 2h). For this functionality, the safety-related time base of each channel (resolution 1ms) is used. Each channel has its own safety-related time base, which is synchronized between the channels. From this, each channel forms the pulses independently. The edge changes are cycle-synchronous. The accuracy of the clock pulses (period duration T) depends on the cycle time: Treal = T + ΔT with ΔT <= cycle time
SPLC_CLOCK_PULSE_1D	SAFEBOOL	Symmetrical clock pulse 1d (High 1d -> Low 1d). Pulse sequence with T/2 = 1 day (T = 2d). For this functionality, the safety-related time base of each channel (resolution 1ms) is used. Each channel has its own safety-related time base, which is synchronized between the channels. From this, each channel forms the pulses independently. The edge changes are cycle-synchronous. The accuracy of the clock pulses (period duration T) depends on the cycle time: Treal = T + ΔT with ΔT <= cycle time
SPLC_POWER_DOWN_EVENT SV_SI	SAFEBOOL	With the rising edge (SAFEFALSE > SAFETRUE), this variable indicates that the standard controller has reported a supply voltage failure. Depending on the type of standard controller (see note below), the safety application in the Safety PLC now has a defined time period to start specific actions for the PowerDown case. The maximum time delay from the occurrence/reporting of the PowerDown event to the handling of the PowerDown event is the duration of the cycle time. Note Whether the PowerDown event is supported depends on whether or not the structure of the standard controller contains an internal UPS. This is currently the case for the controller types NFC482, RFC4072, BPC, and AXC F 3152 with SPLC1000.
SPLC_SYS_TICK_CNT	SAFEDINT	Indicates the number of Safety PLC cycles processed. The counter overflows at 0x7FFFFFFF and restarts automatically at 0x00000000. Value range: 0 ... +2,147,483,647 then start again with 0. The duration until overflow depends on the cycle time. With a cycle time of 5 ms, the counter overflows after approximately 124.27 days.

System variable	Type	Description
FDEV_DYN_READY	SAFEBOOL	Input variable that indicates the successful assignment of the F_Dest_Add to the F-Device. SAFETRUE: The address stored in the variable FDEV_DYN_REQ_F_DST has been applied and is now the valid F_Dest_Add. SAFEFALSE: Assignment of F_Dest_Add is not (yet) valid. Edge SAFETRUE > SAFEFALSE when FDEV_DYN_SET_REQ_F_DST switches from SAFETRUE to SAFEFALSE.
FDEV_DYN_ERROR	SAFEBOOL	Input variable which indicates an error during the assignment of the F_Dest_Add. SAFETRUE: An error has been detected. The related error code can be read from the variable FDEV_DYN_DIAGCODE. SAFEFALSE: No error has been detected.
FDEV_DYN_USED_F_DST	SAFEDINT	Input variable that displays the currently set F_Dest_Add of the F-Device. The value of this variable must be interpreted taking other system variables into account: If FDEV_DYN_MODE_F_DST = FALSE (no dynamic but static address assignment): Display of the configured F_Dest_Add. If the F-Device has not been parameterized, the value is 0. If FDEV_DYN_MODE_F_DST = TRUE: Display of the F_Dest_Add in FDEV_DYN_REQ_F_DST from rising edge of FDEV_DYN_SET_REQ_F_DST (edge-controlled variable for assigning the address). The assigned address value is kept even after FDEV_DYN_SET_REQ_F_DST changes back to FALSE.
FDEV_DYN_USED_F_SRC	SAFEDINT	Input variable that displays the parameterized/used F_Source_Add after the F parameter block of the superimposed controller (i.e., the new F-Host) has been received.
FDEV_DYN_DIAGCODE	SAFEWORD	Diagnostic message. The message/error codes are described in the table below
FDEV_DYN_MODE_F_DST	SAFEBOOL	State-controlled output variable that controls the source of the F_Dest_Add to be used by the F-Device and thus switches the function on/off. Note The variable is only evaluated if the F-Device is in Stop state. SAFEFALSE: Function is not enabled and the F-Device gets its F_Dest_Add from the parameter value set in the 'Safety Parameters' editor of the controller node in the PLANT. Edge SAFEFALSE > SAFETRUE: No action, wait for rising edge of variable FDEV_DYN_SET_REQ_F_DST. SAFETRUE: The F_Dest_Add set in the variable FDEV_DYN_REQ_F_DST is used. Edge SAFETRUE > SAFEFALSE: The F-Device applies the F_Dest_Add configured in the project and carries out a new initialization of the local F-Device.
FDEV_DYN_SET_REQ_F_DST	SAFEBOOL	Edge-controlled output variable that requests the setting of the F-Dest_Add. Note The variable is only evaluated if the F-Device is in Stop state. Edge SAFEFALSE > SAFETRUE: The F-Device applies the F_Dest_Add from the variable FDEV_DYN_REQ_F_DST and carries out a new initialization. Edge SAFETRUE > SAFEFALSE: No action, the F-Device remains in its state.
FDEV_DYN_REQ_F_DST	SAFEDINT	Output variable that contains the F_Dest_Add to be used next for the F-Device. The transfer only takes place on the rising edge of the variable FDEV_DYN_SET_REQ_F_DST.

Code (hex)	Meaning	Remedy
0000	The function is not activated.	Proceed as follows in your safety application program: Write the new F_Dest_Add to the variable FDEV_DYN_REQ_F_DST. To activate the function, set FDEV_DYN_MODE_F_DST to SAFETRUE. To request the address assignment, set FDEV_DYN_SET_REQ_F_DST to SAFERTRUE.
8000	The function is active. The F_Dest_Add was successfully applied if Error is SAFEFALSE and if the same value is read in FDEV_DYN_USED_F_DST as was written in FDEV_DYN_REQ_F_DST.	If this was the intention, no action is required. If this is an unintentional event, verify the user program and correct it (if required), write the modified safety application program to the Safety PLC and restart the Safety PLC.
C000	Invalid configuration of the function due to an invalid F_Dest_Add specification: The value in the variable FDEV_DYN_REQ_F_DST is invalid (0 or 0xFFFF).	Verify the user program and correct it (if required), write the modified safety application program to the Safety PLC and restart the Safety PLC.
C003	The F_Dest_Add set in FDEV_DYN_REQ_F_DST does not match the F_Dest_Add transferred in the F parameter set. The message can only appear when the next connection to the superimposed F-Host is established.	Verify the user program and correct it (if required), write the modified safety application program to the Safety PLC and restart the Safety PLC.