---
source_files:
  - Common/DTS.Common/Enums/TTS/TTSEnums.cs
generated_at: "2026-04-16T03:21:01.092126+00:00"
model: "Qwen/Qwen3-Coder-Next-FP8"
schema_version: 1
sha256: "d044aea8e131ba46"
---

# Documentation: `DTS.Common.Enums.TTS.TTSEnums`

## 1. Purpose  
This module defines enumerations and a custom attribute used to manage field-level metadata for TTS (likely *Test & Test System* or *Twin-Tee Sensor*) import configurations, specifically in the context of Toyota-specific sensor channel definitions. It addresses issue #18396, where TTS import files contain a large number of columns, leading to confusion about which fields are actively used. The `FieldSupportLevel` enum and `FieldSupportAttribute` allow developers to declaratively mark enum fields as `RequiredParameter`, `RemainedButNotUsed`, or `RemovedParameter`, enabling runtime introspection to filter or validate fields during import processing.

## 2. Public Interface  

### `FieldSupportLevel`  
**Type**: `enum`  
**Values**:  
- `RequiredParameter`: Field is actively required and used.  
- `RemainedButNotUsed`: Field exists in the data model/import but is not currently used.  
- `RemovedParameter`: Field has been deprecated and should be ignored.  

### `FieldSupportAttribute`  
**Type**: `class` (custom attribute)  
**Namespace**: `DTS.Common.Enums.TTS`  
**Usage**: `[FieldSupport(FieldSupportLevel)]` applied to enum fields.  
**Properties**:  
- `SupportLevel` (`FieldSupportLevel`): Gets or sets the support level assigned to the attributed field.  
**Methods**:  
- `FieldSupportAttribute(FieldSupportLevel value)`: Constructor.  
- `static FieldSupportLevel GetSupportLevel(Enum genericEnum)`: Returns the `FieldSupportLevel` for a given enum value by reflecting on its `FieldSupportAttribute`. If no attribute is present, defaults to `FieldSupportLevel.RemovedParameter`.  

### `ToyotaFieldOrder`  
**Type**: `enum`  
**Purpose**: Defines the column order (0-based index) for fields in Toyota TTS import files. Each field is annotated with a `FieldSupportAttribute` indicating its current support status.  
**Key Fields (selected)**:  
- `ChannelNumber` (0) → `RequiredParameter`  
- `SensorID` (5) → `RemainedButNotUsed`  
- `InitialOffsetVoltageTolerance` (17) → `RemovedParameter`  
- `KyowaSpecificField_1` (32) → `RemovedParameter` (with FogBugz reference)  

### `ToyotaBridgeType`  
**Type**: `enum`  
**Purpose**: Represents supported bridge configurations for sensors.  
**Values**:  
- `FullBridge`, `HalfBridge`, `Voltage`, `PotentionmeterFullBridge`, `PotentionmeterHalfBridge`, `IRTRACC`, `LinearChestPot`  
**Note**: Values use `[Description]` attributes (from `System.ComponentModel`) but no `FieldSupportAttribute`; support level is not explicitly declared here.  

### `ToyotaZeroMethods`  
**Type**: `enum`  
**Purpose**: Defines zeroing methods for sensor calibration.  
**Values**:  
- `None` (0)  
- `AverageOverTime` (1)  
- `UsePreEventDiagnosticsZero` (2)  
**Note**: Values use `[Description]` attributes (e.g., `"0"`, `"1"`) but no `FieldSupportAttribute`; support level is not explicitly declared here.  

## 3. Invariants  
- **`FieldSupportAttribute.GetSupportLevel(Enum)` behavior**:  
  - Always returns a valid `FieldSupportLevel`.  
  - If the provided enum value has no `FieldSupportAttribute` applied, returns `FieldSupportLevel.RemovedParameter` as a safe default.  
- **`ToyotaFieldOrder` fields**:  
  - Each field must have exactly one `FieldSupportAttribute` (enforced by design, though not compile-time validated).  
  - The integer values are fixed and correspond to column indices in the TTS import file (0–32).  
- **`ToyotaBridgeType` and `ToyotaZeroMethods`**:  
  - No `FieldSupportAttribute` is applied to any of their fields. Their support status is *not* managed by this module and must be handled elsewhere (e.g., in documentation or other attributes).  

## 4. Dependencies  
**Dependencies *of* this module**:  
- `System` (core runtime)  
- `System.ComponentModel` (for `[Description]` attribute used in `ToyotaBridgeType` and `ToyotaZeroMethods`)  
- `System.Linq` (used in `FieldSupportAttribute.GetSupportLevel` via `.Any()` and `.ElementAt()`)  

**Dependencies *on* this module**:  
- Not specified in source, but implied usage:  
  - TTS import logic (e.g., a parser or validator) likely consumes `FieldSupportAttribute.GetSupportLevel()` to filter columns.  
  - UI or configuration tools may use `ToyotaFieldOrder` to map UI controls to import columns.  
  - `ToyotaBridgeType` and `ToyotaZeroMethods` are likely used in sensor configuration classes (not shown here).  

## 5. Gotchas  
- **Default support level**: `FieldSupportAttribute.GetSupportLevel(Enum)` silently defaults to `RemovedParameter` for enums *without* the attribute—this may mask missing annotations.  
- **Reflection overhead**: `GetSupportLevel` uses reflection (`GetMember`, `GetCustomAttributes`) on every call. Not suitable for high-frequency use without caching.  
- **`ToyotaBridgeType`/`ToyotaZeroMethods` lack `FieldSupportAttribute`**: Their support status is undefined in this module. Developers must infer or document separately.  
- **Typos in enum names**: `PotentionmeterFullBridge` and `PotentionmeterHalfBridge` are misspelled (should be *Potentiometer*).  
- **Historical references**: `KyowaSpecificField_1` includes a FogBugz URL (`http://fogbugz/fogbugz/default.asp?5433`), which may be internal-only and inaccessible externally.  
- **No validation of `FieldSupportAttribute` placement**: The attribute is only valid on fields (`AttributeTargets.Field`), but misuse (e.g., on properties) will compile but fail at runtime in `GetSupportLevel`.