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State Change#

Overview#

The EquipmentChangeState event is triggered when CAMX equipment state changes. The integration automatically processes this event through the StateChange automation workflow, which validates the state transition and updates the resource state in MES via the SEMI-E10 state model.

Message Fields#

Field Type Description
eventId String Event identifier for traceability
currentState String New equipment state (IPC-2541 format)
previousState String Previous equipment state (IPC-2541 format)
Extensions Object Optional custom data from equipment

Workflow Processing#

Equipment Event (EquipmentChangeState)
    ↓
equipmentEvent task → Parse currentState, previousState, eventId
    ↓
doStateChange subworkflow
    ↓
IoTStateModelContext → Map equipment state to SEMI-E10
    ↓
AdjustObjectState → Update resource state in MES
    ↓
Result logging

Detailed Steps#

  1. Message Reception: Driver receives EquipmentChangeState message from broker
  2. State Extraction: equipmentEvent task extracts currentState, previousState, eventId, and Extensions
  3. Validation: codeExecution task validates:
  4. useCAMXToChangeState feature flag is enabled
  5. currentState is not null or empty
  6. previousState is not null or empty
  7. Resource Resolution: retrieve task gets ResourceName for the resource context
  8. Subworkflow Invocation (if validation passes): Triggers doStateChange subworkflow with:
  9. currentState (IPC-2541 format, e.g., "READY-PROCESSING-ACTIVE")
  10. previousState (IPC-2541 format)
  11. State Mapping: Maps equipment state to SEMI-E10 state using IoTStateModelContext configuration
  12. State Update: Calls AdjustObjectState API with mapped SEMI-E10 state
  13. Error Handling: Connection errors evaluated for retry eligibility; non-retriable errors logged
  14. Event Logging: Logs state transition with eventId for traceability

State Mapping#

Equipment states are mapped to SEMI-E10 states using IoTStateModelContext:

Equipment State (IPC-2541) Description
READY-PROCESSING-ACTIVE Equipment actively processing material
READY-IDLE-STARVED Equipment ready but waiting for input material
READY-IDLE-BLOCKED Equipment blocked and unable to process
IoTStateModelContext Example IPC-2541 to SEMI E10 
{
    "<ST>IoTStateModelContext": {
        "1": {
            "Driver": "CAMX",
            "StateModel": "SEMI E10",
            "ResourceType": "",
            "Resource": "",
            "StateModelState": "Productive",
            "Values": "READY-PROCESSING-ACTIVE"
        },
        "2": {
            "Driver": "CAMX",
            "StateModel": "SEMI E10",
            "ResourceType": "",
            "Resource": "",
            "StateModelState": "Standby",
            "Values": "READY-IDLE-STARVED"
        },
        "3": {
            "Driver": "CAMX",
            "StateModel": "SEMI E10",
            "ResourceType": "",
            "Resource": "",
            "StateModelState": "Scheduled Down",
            "Values": "READY-IDLE-BLOCKED"
        }
    }
}

Resource Instantiation

An instantiated MES resource is required to properly assign the properties to it

Configuration#

For state change processing, configure the following:

1. Feature Flag in IoTMetadataDefinition#

Configuration Key Type Description
useCAMXToChangeState String Enable state change processing; set to "EquipmentChangeState" to enable

Validation Flow

State changes are only processed if useCAMXToChangeState is configured in IoTMetadataDefinition. Without this configuration, state change events are logged but not processed by the StateChange workflow.

Error Handling#

Pre-Validation Errors (No API Call)#

These errors prevent AdjustObjectState API invocation:

Error Cause Behavior
Feature Disabled useCAMXToChangeState not configured Log validation error, complete without API call

API Errors (After AdjustObjectState Call)#

Error Cause
Connection Refused MES system unavailable
Invalid State State not valid for resource
Resource Locked Resource currently locked

Troubleshooting#

State Changes Not Processed#

Equipment sends EquipmentChangeState but resource state doesn't update in MES

  • Verify useCAMXToChangeState configuration exists in IoTMetadataDefinition
  • Restart Automation Controller after adding configuration
  • Check controller logs for validation errors
  • Verify state mapping exists in IoTStateModelContext for the equipment state

Validation Errors#

Controller logs show validation error messages

  • Ensure both currentState and previousState are provided in message
  • Verify states are not null or empty strings

AdjustObjectState Failures#

State update called but fails in MES

  • Verify resource exists in MES and is correctly configured
  • Check resource has SEMI-E10 state model assigned
  • Check that mapped SEMI-E10 state is valid for the resource type