Continuous reading

[tomjoro]

The ADS1X15 chips have two modes: single-shot and continuous. Single-shot powers down between reads, so the maximum read rate is around 33 times per second (not verified). Reading at a higher rate requires continuous mode.

In continuous mode the inputs must be selected and enabled. After that the fsr can be read at anytime and up to the maximum rate in the spec sheet.

Currently the code doesn't show how to do this.

[tomjoro]

This seems to work.

def continuous_read_enable(bus, addr, comparison, gain \\ 2048) do
    config = %Config{
      performing_conversion: false,
      mode: :continuous,
      mux: comparison,
      gain: gain
    }
    set_config(bus, addr, config)
  end

In continuous mode only the selected inputs can be read.

  def continuous_read(bus, addr) do
    with {:ok, <<val::signed-size(16)>>} <- I2C.write_read(bus, addr, @sensor_register, 2) do
      val = val / 16 # equivalent to val >> 4
      if val > 2047 do   # 0x7FF
        {:ok, val - 4096}  # double 2048
      else
        {:ok, val}
      end
    end
  end