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"?"   The module returns its ID, TEI0015 returns "1" and TEI0016 returns "2"

ADC data acquisition and Fourier transformation Demo

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This demo works with the modules TEI0015 and TEI0016. In this example the ADC of the module measures one million samples
and stores them inside its SD-RAM. The data is collected, converted and shown as graph plot, showing its value and
time behaviour and for the second graph a Fourier transformation is performed, showing the Frequency spectrum.

The user can adjust the pre-amplification and length of the data to be processed.

In this demo the general approach on how to communicate with the module and perform high speed measurements with
the ADC are shown.

Communicating with module:

To communicate with the module, a serial comport port with a speed set to 115200 bits needs to be opened.
Commands consists of a single  character in UTF-8 encoding.
It is good practice to communication with the module following these steps:

  • Open a serial comport
  • Clear the PCs serial comport input buffer of the opened comport
  • Send the desired commands, each one in a single write operation to the comport
  • Close the serial comport as soon as possible

These steps apply also for read operations.

Using the ADC for high speed consecutive measurements

The module provides a method to gather highly accurate consecutive ADC measurements in a single event.
In this mode of operation, one mega sample of ADC values are performed and stored inside the modules
SD-RAM.

The following step should be taken in this mode:

  • Open a serial comport
  • Send the command "1", "2", "4" or "8" for the ADC pre-amplification
  • Send the command "t" to trigger the consecutive measurement
  • Clear the PCs serial comport input buffer of the opened comport
  • Send the command "+" or "*", the module transmits 128 or 16384 Samples of ADC values
  • Read the amount of ADC values in one chunk of 128 or 16384 samples from the serial input buffer of the PC
  • Repeat the reading of chunks to a maximum of 1 mega sample
  • Close the comport

After a trigger event, the one mega sample of data is stored until your retrigger. So processing the data can
be done for each chunk individually or the whole one mega sample.

Information to convert the RAW ADC data into standard integer values.

Module TEI0015 - AD4003BCPZ-RL7

Resolution: 18-bit / 5 nibbles
Maximum sampling rate: 2 MSPS

Order of Values:

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The layout of the ADC circuit is further described in the Analog Devices circuit note CN-0385.

Module TEI0016 - ADAQ7988BCCZ

Resolution: 16-bit / 4 nibbles
Maximum sampling rate: 0.5 MSPS

Order of Values:

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The layout of the ADC circuit is further described in the Analog Devices circuit note CN-0393.