Use Case and Applications

SPX is typically used as a deterministic “plant/device” behind your real client code. The quality gate is a test suite (MiL tests) that drives time explicitly and asserts behavior.

Below are concrete, repo-grounded use cases (models and tests live in spx-examples).

MiL integration tests for Modbus clients

• Template model: thermal_controller__modbus.yaml

• Your Software Under Test: a Modbus TCP client (PLC code, gateway, driver, etc.)

• SPX role: deterministic device state + faults + time control

Docs: Add a communication protocol, Use in Unit Tests (MiL).

Simulate SCPI/ASCII instruments for driver testing

• Template model: multimeter__scpi.yaml

• Your Software Under Test: instrument driver speaking SCPI over TCP

• SPX role: instrument state machine + predictable waveforms/scenarios

Docs: ASCII / SCPI Adapter, Use in Unit Tests (MiL).

MQTT device telemetry regression tests

• Template model: environment_sensor__mqtt.yaml

• Your Software Under Test: telemetry ingestion / rules engine / alerting

• SPX role: controllable publish cadence, payload values, and fault injection

Docs: MQTT Adapter.

BLE device simulation for mobile apps and QA rigs

• Template model: temperature_sensor__ble_gatt.yaml

• Companion process: spx-ble-adapter exposes a real BLE peripheral backed by SPX attributes

Docs: BLE Adapter, BLE Device Simulation Walkthrough.

Snapshot-driven regression suites

• Capture a known-good state as a Snapshot.

• Restore it before a test so every run starts from the same simulation state.

Docs: Snapshots — Getting Started, Snapshots (Core).