=====================
The multimeter module
=====================

Abstraction module for multimeters. The cmd_multimeter module allows the transparent use of a pool of an undefined number of multimeters regardless of maker, model or host-device link technology. Its function is to redirect the requests and orders made to it, to a module that knows how to interface with that particular device.

Presently, the following compatible modules are shipped with Pyrame:

.. toctree::
    :titlesonly:

    Agilent 34401A multimeter <cmd_ag_34401a>
    Keithley 6487 picoammeter <cmd_mm_ki_6487>
    Keithley 6517 picoammeter <cmd_mm_ki_6517>
    Omega iTHX-m temperature / humidity sensor <cmd_om_ithx_m>
    Pfeiffer TPG300 pressure gauge controller <cmd_pf_tpg300>
    LakeShore 421 gaussmeter <cmd_ls_421>

This module is the analog of :doc:`cmd_ps <cmd_ps>` for multimeters. See its documentation for general considerations.

Functions
=========

On top of the mandatory functions listed in :doc:`cmd_ps <cmd_ps>`, the following can be implemented and accessed through cmd_multimeter:

- get_dc_voltage_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_ac_voltage_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_dc_current_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_ac_current_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_2w_resistance_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_4w_resistance_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_frequency_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_period_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_temp_MODEL(*model_id* [, *range* [, *resolution* ]])
- get_rh_MODEL(*model_id* [, *range* [, *resolution* ]])
- timed_acq_MODEL(*model_id*, *value_type*, *nb_measures*, *period* [, *range* [, *resolution* ]])
- get_error_queue_MODEL (*model_id* )

In all cases:
- Magnitudes (i.e.: voltage, current, frequency, etc.), either sent or returned, must be expressed in base units of the International System of Units (V, A, Hertz, etc.).

.. note:: As hinted out by the optional arguments on the list of functions, the arguments passed through to the model function will depend on the capabilities of that particular PS model. cmd_ps uses the API exchange mechanism to determine them. 

API
===

.. automodule:: cmd_multimeter
   :members:
   :member-order: bysource