OpenAFE and OpenAFE Desktop App

Installation

Firstly, it is required to install the OpenAFE library:

• Download library as zip
• In Arduino IDE, go to Sketch>Include Library>Add .ZIP Library and select the recently downloaded OpenAFE library zip file

Finally, it is time to download the OpenAFE Comm:

• Download the OpenAFE Comm as zip
• Do the same process to include this library, go to Sketch>Include Library>Add .ZIP Library and select the recently downloaded OpenAFE Comm library zip file

Now in Arduino IDE, got to File>Examples>openafe_comm>openafe_communication to open openafe_communication.ino example from the openafe_comm libray, and upload it to the Arduino board with the shield.

List of Commands (App to MCU)

Special Commands

• CVW - Cyclic Voltammetry Wave, sends the parameters and start the voltammetry, if possible.
• DPV - Differential Pulse Voltage, sends the parameters and start the voltammetry, if possible.
• SWV - Square Wave Voltammetry, sends the parameters and start the voltammetry, if possible.
• EIS - Impedance Spectroscopy, sends the parameters and start the spectroscopy, if possible.

Standard Commands

Standard commands have CMD preceding the command code in the command message, for example: $CMD,RUN*81.

• RUN - Run (start) the voltammetry process (sequencer only).
• CHK - Check if the AFE is responding properly, reads from the ADIID register.
• DIE - Kills the MCU and AFE, making them 'die' (reset).
• CUR - Set the expected current range.
• TIA - Configures the Transimpedance Amplifier (TIA) gain resistor.

List of Messages (MCU to App)

Special Messages

• SGL - Single point result, has the voltage and current of a single point of the voltammetry.
• EOT - Single point impedance result, has the omega and impedance of a single point of the spectroscopy.
• MLT - Multi point result, has the voltage and current of multiple points of the voltammetry.

Standard Messages

Standard messages have a MSG preceding the message code, for example: $MSG,RDY*3A.

• RDY - Device is ready to receive commands from the App.
• RCD - Message received.
• STR - The voltammetry is starting.

Error Messages

Error messages have a ERR preceding the error message, for example: $ERR,INV*38.

• GEN - General error, may include an error message.
• INV - Invalid command error, for some reson the command is invalid, CRC check error, etc.
• PAR - Parameter error, one of the parameters passed is out of bounds.
• WAV - Wave error, an error has ocurred during the voltammetry process.
• AFE - AFE error, for any reason the AFE IC does not respond properly, e.g. does not pass the health check.

Operation

Below is an illustration of how the OpenAFE (the original library) works with the OpenAFE Desktop App:

+----------------------------------------+
|                 Desktop                |
|  ====================================  |
|  |        OpenAFE Desktop App       |  |
|  ====================================  |
+----------------------------------------+
                ||      /\
               \  /    /  \     USB
                \/      ||
+----------------------------------------+
|  ====================================  |
|  |          OpenAFE Comm            |  |
|  |     +----------------------+     |  |
|  |     |  OpenAFE Interpreter |     |  |
|  |     +----------------------+     |  |
|  ====================================  |
|  |        OpenAFE Executioner       |  |
|  ====================================  |
|                   /\                   |
|                  /  \                  |
|                   ||                   |
|                  \  /                  |
|                   \/                   |
|  ====================================  |
|  |             OpenAFE              |  |
|  ====================================  |
|                Arduino                 |
+----------------------------------------+

OpenAFE Comm

The OpenAFE Comm operates as the translation layer between the OpenAFE functions and the OpenAFE Desktop App. And it should be noted that it sits on top of the OpenAFE library.

OpenAFE Interpreter

This is an internal module of the OpenAFE Comm, it sole purpose is to get the parameters from the command strings OpenAFE Comm passes to it, returning these parameters inside structs, for better readability and ease use.

OpenAFE Executioner

This layer is tasked with calculating the parameters for the AFE IC with the parameters received from OpenAFE Comm, checking if they are not out of bounds, feed the sequencer and start the voltammetry, it is also tasked with sending the data from the AFE to the OpenAFE Comm.

OpenAFE Shared

This header file has definitions for constants and structs that are used on OpenAFE Comm, Interpreter and Executioner. But it is not used in the original OpenAFE.

OpenAFE Error Codes

This is a header file that contains the definition of multiple errors, and is used by Comm, Interpreter and Executioner.

It might be added to the OpenAFE root library in the future.