# Load and Unload Solder Paste from the Solder Paste Printer

## Overview

This feature enables the load and unload of solder paste consumable materials on Solder Paste Printer machines, triggered by Fuji Nexim equipment events.

### Relevant Artifacts

| Name                                                                         | Type       | Is Mandatory | Data Type | Description                                                                                              |
| :--------------------------------------------------------------------------- | :--------- | :----------: | :-------- | :------------------------------------------------------------------------------------------------------- |
| IoTMetadataDefinition                                                        | SmartTable | Yes          |           | Metadata configuration used to enable or bypass the solder handling feature per resource.                |
| [IoTFujiNeximHandleSolder](../../artifacts/dees.md#iotfujineximhandlesolder) | DEE        | Yes          |           | Attaches or detaches solder paste material from the target consumable feeder on a specified MES resource.|
| `/IoT/FUJI/SolderPasteFeederType/`                                           | Config     | Yes          |           | Determines the target consumable feeder.                                                                 |

## How It Works

When a `LOADSOLDER` or `UNLOADSOLDER` event is received from the Fuji Nexim equipment, the following steps are executed:

### Area Feature Checks

- Resolves the MES Sub-Resource Name using the pattern:
  `FUJI_LineNameMachineName_{EquipmentLineName}_{EquipmentMachineName}`.

### Resource Feature Checks

- Checks whether the `UseFujiToHandleSolder` feature is enabled for the resolved MES Resource in the `IoTMetadataDefinition` Smart Table.

### MES Operations

If the feature is enabled, the Automation Controller calls the DEE [IoTFujiNeximHandleSolder](../../artifacts/dees.md#iotfujineximhandlesolder), which performs the following:

- Validates the solder material identified by `SolderID` and confirms its Product matches `SolderName`.
- Determines the target consumable feeder using the configuration key `/IoT/FUJI/SolderPasteFeederType/`.
- Performs the operation based on the `Operation` input:

    **Load:**

    - If the material is already attached to the correct feeder on the correct resource, no action is performed.
    - If the material is attached to a different feeder, it is detached first.
    - If the target feeder already has a different material attached, it is detached first.
    - The solder material is then attached to the target feeder.
    - If the material does not exist in MES, an error is thrown.

    **Unload:**

    - If the material is not attached, no action is performed.
    - If the target feeder does not belong to the resource, no action is performed.
    - Otherwise, the solder material is detached from the target feeder.

- Sends a `LOADSOLDER_ACK` or `UNLOADSOLDER_ACK` message back to the equipment with:
    - A result (`0` = Ok, `1` = NOk) for the operation.

**Error Handling**
If any step fails during the DEE operation (e.g. material not found, feeder not found, configuration missing), the operation is considered failed and an error is returned to the equipment.

**Bypass Condition**
If `UseFujiToHandleSolder` is set to `False` or is not defined in `IoTMetadataDefinition`, the DEE call is bypassed entirely and no MES operation is performed.

### Assumptions

The `IoTMetadataDefinition` Smart Table must be configured with the following entry for each station:

| Resource                    | ResourceType | Area           | Name                  | Value |
| --------------------------- | ------------ | -------------- | --------------------- | ----- |
|                             |              | Fuji Line Area | FUJI_LineNameMachineName_{EquipmentLineName}_{EquipmentMachineName} | MES ResourceName    |
| MES Fuji Station X Resource |              |                | UseFujiToHandleSolder | True  |