elua/doc/eluadoc/refman_gen_adc.lua

-- eLua reference manual - ADC

data_en = 
{

  -- Title
  title = "eLua reference manual - ADC",

  -- Menu name
  menu_name = "adc",

  -- Overview
  overview = [[This module contains functions that access analog to digital converter (ADC) peripherals.</p>
  <p>When utilizing this module, acquiring ADC data is a two step process: requesting sample conversions (using $adc.sample$) and extraction of conversion results from a conversion buffer (using $adc.getsample$, $adc.getsamples$ or $adc.insertsamples$). Various configuration parameters are available to set conversion rate, how results are extracted from the buffer and how these results are processed prior to extraction.</p>
  <p>This module can be utilized if the device in use has a supported ADC peripheral (see @status.html@status@ for details) and if ADC functionality is enabled at build time (see @building.html@building@).</p>
<p><span class="warning">IMPORTANT</span>: Platform support varies for this module (see @status.html#plat_notes@status notes@ for details) .
  ]],

  -- Functions
  funcs = 
  {
    { sig = "#adc.sample#( id, count )",
      desc = "Initiate conversion and buffering of samples on an ADC channel.",
      args = 
      {
        "$id$ - ADC channel ID. Optionally, this may be a table containing a list of channel IDs (i.e.: {0, 2, 3}), allowing synchronization of acquisition. NOTE: This acceptance of mixed types is only for the sample function.",
        "$count$ - number of samples to acquire and place in buffer."
      }
    },
    { sig = "sample = #adc.getsample#( id )",
      desc = "Get a single conversion value from the buffer associated with a given channel.",
      args = 
      {
        "$id$ - ADC channel ID."
      },
      ret = "$sample$ - numeric value of conversion, or nil if sample was not available."
    },
    { sig = "samples = #adc.getsamples#( id, count )",
      desc = "Get multiple conversion values from the buffer associated with a given channel.",
      args = 
      {
        "$id$ - ADC channel ID.",
        "$count$ - optional parameter to indicate number of samples to return. If not included, all available samples are returned."
      },
      ret = "$samples$ - table containing integer conversion values. If not enough samples are available, remaining indices will be nil."
    },
    { sig = "#adc.insertsamples#( id, table, idx, count )",
      desc = "Get multiple conversion values from a channel's buffer, and write them into a table.",
      args = 
      {
        "$id$ - ADC channel ID.",
        "$table$ - table to write samples to. Values at $table$[$idx$] to $table$[$idx$ + $count$ -1] will be overwritten with samples (or nil if not enough samples are available).",
        "$idx$ - first index to use in the table for writing samples.",
        "$count$ - number of samples to return. If not enough samples are available (after blocking, if enabled) remaining values will be nil."
      }
    },
    { sig = "maxval = #adc.maxval#( id )",
      desc = "Get the maximum value (corresponding to the maximum voltage) that can be returned on a given channel.",
      args = 
      {
        "$id$ - ADC channel ID."
      },
      ret = "$maxval$ - maximum integer conversion value (based on channel resolution)"
    },
    { sig = "clock = #adc.setclock#( id, clock, timer_id )",
      desc = "Set the frequency (number of samples per second) at which voltages will be converted into samples.",
      args = 
      {
        "$id$ - ADC channel ID.",
        "$clock$ - frequency to acquire samples at in Hz (number of samples per second), 0 to acquire as fast as possible.",
        "$timer_id$ - Timer channel ID to use to control ADC conversion. <strong>Note:</strong> At this time, a timer selection will apply to all channels on a given ADC peripheral."
      },
      ret = "$clock$ - actual acquisition frequency to be used"
    },
    { sig = "status = #adc.isdone#( id )",
      desc = "Check whether samples are still being acquired on a channel.",
      args = 
      {
        "$id$ - ADC channel ID."
      },
      ret = "$status$ - 1 if no samples are being acquired, 0 if samples are pending acquisition."
    },
    { sig = "#adc.setblocking#( id, mode )",
      desc = "Set whether or not functions that request converted samples should wait for requested samples or return immediately with what is available.",
      args = 
      {
        "$id$ - ADC channel ID.",
        "$mode$ - 1 if requests to get samples should block until requested samples are available or sampling has completed, 0 to return immediately with available samples"
      },
    },
    { sig = "#adc.setsmoothing#( id, length )",
      desc = "Set the length of the moving average filter. When $length$ is greater than 1, samples pulled from the conversion buffer will be averaged with the preceding $length$ - 1 buffered values.",
      args = 
      {
        "$id$ - ADC channel ID.",
        "$length$ - number of preceding samples to include in moving average filter (must be a power of 2). If 1, filter is disabled. When enabled, a filter buffer is filled before the main conversion buffer, so that averages are always over the same number of samples."
      }
    }
  }
}

data_pt = data_en