Introduction

What is the SynapseLink Protocol?

The SynapseLink Protocol is remote procedure call (RPC) protocol for EvoluxIoT Ecosystem. It allows the communication between the EvoluxIoT Ecosystem and the Synapse Devices by using a custom transport protocol such as MQTT which communicates through commands.

How it works

Command structure

A commands allows the communication between the EvoluxIoT Ecosystem and the Synapse Devices. It invokes a action on the Synapse Device and returns the result of it.

The structure of a command sent from the EvoluxIoT Ecosystem to the Synapse Device is:

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Command Syntax

• COMMAND NAME:,:COMMAND PARAMETER 1:,:COMMAND PARAMETER 2:,: (...) :,:EVENT ID
• !COMMAND DECIMAL:,:COMMAND PARAMETER 1:,:COMMAND PARAMETER 2:,: (...) :,:EVENT ID

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Command Parameters

• !: Indicates if the message is sent from the Synapse Device to the EvoluxIoT Ecosystem. (not included when originated from the Ecosystem Portal)
• COMMAND NAME/DECIMAL: The name/decimal of the command to be executed on the Synapse Device.
• COMMAND PARAMETER: The parameters of the command to be executed on the Synapse Device. (the number of parameters depends on the command executed)
• EVENT ID: The id of the event to be sent back to the EvoluxIoT Ecosystem (increments by one at each message between both parties).

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Practical example

1. The EvoluxIoT Ecosystem sends a command to the Synapse Device.

   For example a user wants to display a message on the display of the Synapse Device and in the Ecossystem Portal the user enters the text and presses show.

   The ecossystem receives the instruction from the user and builds a equivalent command to be sent to the Synapse Device:

   • DISPLAYWRITE is the command to be executed
   • Hello World is the paramenter of DISPLAYWRITE which contains the text to be displayed
   • 0 is the event id, assuming that this is the first communication between the Ecosystem and the Synapse Device.

   Ecosystem Portal outputs DISPLAYWRITE:,:Hello World:,:0 to Synapse Device

2. The Synapse Device receives the command and sends a acknowledge back to the EvoluxIoT Ecosystem.

   When the Synapse Device receives a command, the Ecosystem Portal expects a acknowledge back from the Synapse Device to ensure that the command was received successfully and it's being executed on the Synapse Device:

   • ! is always included when it's the Synapse Device communicating with the Ecosystem Portal
   • 2 is the command acknowledge represented in decimal format (0x02 in hexadecimal format)
   • The following parameters are the same as the command sent by the Ecosystem Portal except the event id received
   • 1 is the event id, incremented by one since one message was sent from the Ecosystem Portal to the Synapse Device before.

   Synapse Device outputs !2:,:DISPLAYWRITE:,:Hello World:,:1 to Ecosystem Portal

   Ecosystem Portal knows that the command was received successfully, it's being executed on the Synapse Device and gets ready for receving the command status response.

3. The Synapse Device executes the command and sends the result back to the EvoluxIoT Ecosystem.

Commands Available

Code Hex/Dec	Command Name	Command Description
0x00/0	MAXVERSION	Returns the maximum version of the SynapseLink Protocol supported by the Synapse Device
0x01/1	HEARTBEAT	Checks if the Synapse Device is online and responsive to requests
0x02/2	ACKNOWLEDGE	Returns the acknowledge of the command sent by the Ecosystem Portal
0x03/3	REBOOT	Reboots the Synapse Device
0x04/4	DIGITALREAD	Reads the value of a digital pin
0x05/5	DIGITALWRITE	Writes a value to a digital pin
0x06/6	ANALOGREAD	Reads the value of a analog pin
0x07/7	ANALOGWRITE	Writes a value to a analog pin
0x08/8	PWMREAD	Reads the value of a pwm pin
0x09/9	PWMWRITE	Writes a value to a pwm pin
0x0A/10	DISPLAYWRITE	Writes a text to the display of the Synapse Device