==============
Sensor Polling
==============

The CMSW application polls sensors from PDUs via SNMP and cooling system via Modbus.

PDU Sensor Polling
==================

PDUs are polled asynchronously using SNMP. Configuration is defined in ``config.yaml``:

.. code-block:: yaml

    cmsw:
      polling_intervals:
        sensor_polling: 5  # seconds between polling cycles
      pdu:
        device_definition: drivers/pdu/device_definitions/enlogic.yaml
        community: public
        pdus:
          - id: PDU1
            host: 10.0.11.11
            port: 161
          ## Uncomment if 2 PDUs present
          # - id: PDU2
          #   host: 10.0.11.12
          #   port: 162
                

Sensor Names
------------

Sensor names are defined in device definition YAML files located in ``drivers/pdu/device_definitions/``. Common sensors include:

- ``pduTemperature`` - PDU temperature in Celsius
- ``pduHumidity`` - PDU humidity as percentage
- ``pduPort{}Current`` - Port current in hundredths of Amps (e.g., ``pduPort1Current``)
- ``pduPort{}ActivePower`` - Port active power (e.g., ``pduPort1ActivePower``)
- ``pduPhase{}Voltage`` - Phase voltage in Volts (e.g., ``pduPhase1Voltage``)

API Access
==========

Sensor readings are accessible via the REST API interface.

To retrieve all sensor readings at once, run this:

.. code-block:: bash

    curl -s <host>:<port>/readings

To retrieve a specific PDU reading, e.g. current in port 1 of PDU1, run this:

.. code-block:: bash

    curl -s <host>:<port>/readings/pdus/PDU1/pduPort1Current


Cooling System Sensors Polling
==============================

To be implemented.