---
title: "IRIV IO Controller Series: RS-485 (Modbus) → Ethernet → Cloud (Blynk / ThingSpeak / MQTT) + Agricult"
url: "https://maker.wiznet.io/irina/projects/iriv-io-controller-series-rs-485-modbus--ethernet--cloud-blynk-thingspeak-mqtt-agricult/"
markdown_url: "https://maker.wiznet.io/irina/projects/iriv-io-controller-series-rs-485-modbus--ethernet--cloud-blynk-thingspeak-mqtt-agricult/md"
type: "UCC: User Created Content"
author: "Hussien Jawhar Sathik"
editor: "WIZnet"
editor_url: "https://maker.wiznet.io/"
original_author: "Hussien Jawhar Sathik"
published: "2025-08-27"
language: "en"
likes: 0
views: 2468
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---
# IRIV IO Controller Series: RS-485 (Modbus) → Ethernet → Cloud (Blynk / ThingSpeak / MQTT) + Agricult
> Read RS-485 Modbus sensors on IRIV, send data via WIZnet W5x00 to Blynk, ThingSpeak, and MQTT (Adafruit IO), then build an irrigation automation example.
Original author: Hussien Jawhar Sathik
## Article
This series shows how to read RS-485 (Modbus RTU) sensors on the **IRIV IO Controller** and send data over Ethernet using a **WIZnet W5x00** driver (CircuitPython) to three cloud paths—**Blynk**, **ThingSpeak**, and **MQTT (Adafruit IO)**—and then apply it to an **agriculture automation** example (moisture-based pump control).
H/W : IRIV IO Controller -
## COMPONENTS
- IRIV IO Controller × 1 (RJ-45 Ethernet, RS-485, DO relay): with W5500
- RS-485 (Modbus RTU) Temp/Humidity Sensor × 1
- RS-485 Soil Sensor (Moisture/Temp/EC) × 1 (for automation section)
- 24 V DC Industrial Relay × 1 (pump/valve control)
- Ethernet network (DHCP recommended)
**Clicking the picture redirects you to the maker’s website.**
| [](https://maker.wiznet.io/irina/projects/iriv%2Dio%2Dcontroller%2Diot%2Dgateway%2D%2Dblynk/) | [](https://maker.wiznet.io/irina/projects/iriv%2Dio%2Dcontroller%2Diot%2Dgateway%2D%2Dthingspeak/) | [](https://maker.wiznet.io/irina/projects/iriv%2Dio%2Dcontroller%2Diot%2Dgateway%2D%2Dmqtt/) | [](https://maker.wiznet.io/irina/projects/automation%2Dof%2Dagriculture%2Dwith%2Diriv%2Dio%2Dcontroller/) |
| --- | --- | --- | --- |
## Table of Contents
1. Prerequisites & Common Architecture
2. Common Code Skeleton (W5x00 + Modbus)
3. Cloud Integrations and descriptions
1. Blynk (Virtual Pins V0/V1)
2. ThingSpeak (field1/field2)
3. MQTT (Adafruit IO)
4. Agriculture Automation (Moisture-based Pump Control)
5. Which Platform When? (Quick Comparison)
6. Troubleshooting & Checklist
7. Future Content Directions
## 1. Prerequisites & Common Architecture
- **Hardware**: IRIV IO Controller; RS-485 sensors (T/RH, soil moisture/EC/temp); 24 V relay; Ethernet.
- **CircuitPython stack**: `adafruit_wiznet5k`, `adafruit_connection_manager`, `adafruit_requests`, `uModbus` (+ `adafruit_minimqtt` for MQTT).
- **Flow**: RS-485 Modbus read → scale/convert → upload (HTTP/MQTT) → visualize/control on cloud.
## 2. Common Code Skeleton (W5x00 + Modbus)
```python
import board, busio, digitalio
import adafruit_connection_manager, adafruit_requests
from adafruit_wiznet5k.adafruit_wiznet5k import WIZNET5K
from umodbus.serial import Serial as ModbusRTUMaster
# Ethernet (DHCP)
cs = digitalio.DigitalInOut(board.W5500_CS)
spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)
eth = WIZNET5K(spi, cs)
pool = adafruit_connection_manager.get_radio_socketpool(eth)
ssl = adafruit_connection_manager.get_radio_ssl_context(eth)
requests = adafruit_requests.Session(pool, ssl)
# Modbus RTU master (UART)
host = ModbusRTUMaster(tx_pin=board.TX, rx_pin=board.RX)
# Example registers (may vary by sensor)
temperature = host.read_holding_registers(1, 1, 1)[0] / 10.0
humidity = host.read_holding_registers(1, 0, 1)[0] / 10.0
```
## 3. Cloud Integrations and descriptions
### 3.1 Blynk (Virtual Pins V0/V1) : [link](https://maker.wiznet.io/irina/projects/iriv%2Dio%2Dcontroller%2Diot%2Dgateway%2D%2Dblynk/)
Create a Blynk device & dashboard, get your **Auth Token**, add V0=Temperature and V1=Humidity. Then push:
```plaintext
http://blynk.cloud/external/api/update?token=&V0=&V1=
```
### Descriptions
The first example demonstrates integration with the **Blynk platform**.
The IRIV IO Controller reads sensor data via RS-485 and then sends it through Ethernet using simple **HTTP GET requests** to the Blynk cloud.
In the code, the values are mapped to **virtual pins V0 and V1** for temperature and humidity.
As a result, you can see the same data in both the local terminal and the Blynk mobile app.
The key point here is that **remote monitoring can be achieved with just a lightweight API setup**.
### 3.2 ThingSpeak (field1/field2): [link](https://maker.wiznet.io/irina/projects/iriv%2Dio%2Dcontroller%2Diot%2Dgateway%2D%2Dthingspeak/)
Create a **ThingSpeak Channel**, copy the **Write API Key**, map fields, then call:
```plaintext
http://api.thingspeak.com/update?api_key=&field1=&field2=
```
### Descriptions
The second example uses **ThingSpeak**.
After creating an account, you generate a channel and obtain a **Write API Key**, which is placed in the code.
Like Blynk, the IRIV IO Controller reads sensor data over RS-485 and sends it via Ethernet with **HTTP requests**.
The main difference is that ThingSpeak automatically **plots the data as graphs** and stores it for analysis.
This shows that ThingSpeak is well-suited for **data logging and analytics-focused IoT services**.
### 3.3 MQTT (Adafruit IO):[link](https://maker.wiznet.io/irina/projects/iriv%2Dio%2Dcontroller%2Diot%2Dgateway%2D%2Dmqtt/)
Create an Adafruit IO account, copy the **AIO Key**, put credentials in `settings.toml`, create feeds *Temperature*/*Humidity*, then publish:
```plaintext
# Topics
username/feeds/Temperature ←
username/feeds/Humidity ←
```
## Descriptions
The third example highlights the **MQTT protocol**.
Here, **Adafruit IO** is used as the MQTT broker.
Sensor data is published to dedicated feeds, for example, **‘Temperature’** and **‘Humidity’**.
The advantage of MQTT is its **lightweight publish/subscribe model**, which makes it highly scalable and reliable for large IoT deployments.
So while the first two methods rely on HTTP, this example demonstrates a more **industrial, scalable IoT architecture**.
## 4. Agriculture Automation (Moisture-based Pump Control): [link](https://maker.wiznet.io/irina/projects/automation%2Dof%2Dagriculture%2Dwith%2Diriv%2Dio%2Dcontroller/)
- **Registers (example)**: Ambient RH=reg0 (÷10), T=reg1 (÷10); Soil T=reg6 (÷100), Moisture=reg7 (÷100), EC=reg8.
- **Actuation**: Drive a 24 V relay from DO0 to control a pump/valve.
- **Rule**: If `SoilMoisture ≥ threshold` → PUMP ON, else OFF. Report values & relay state to dashboard (e.g., Blynk V0–V5)
### Descriptions
“The final example is a **real-world application: agricultural automation**.
Multiple RS-485 sensors, measuring soil moisture, temperature, pH, and EC, feed data into the IRIV IO Controller.
Based on the conditions, the controller **drives a relay to activate a water pump**.
Meanwhile, the same sensor data is also forwarded to** Blynk** for visualization.
This completes the cycle of **sensing → control → monitoring**, showing how IRIV IO Controller can be applied directly in agriculture.
It demonstrates not just data acquisition, but **closed-loop automation** in practice.”
## 5. Which Platform When? (Quick Comparison)
| Goal | Platform | Why |
| --- | --- | --- |
| Mobile dashboard / quick UI | **Blynk** | Virtual pins + widgets; fast setup |
| Time-series logging / charts | **ThingSpeak** | Field-based HTTP updates; built-in plots |
| Real-time events / two-way | **MQTT (Adafruit IO)** | Pub/Sub; scalable & controllable |
| Edge automation (pump) | **Blynk + local logic** | Cloud viz + on-device decisions |
## 6. Troubleshooting & Checklist
- **Modbus values off**: Check slave addr, registers (0/1/6/7/8), baud/parity/stop, scaling (÷10/÷100).
- **No network**: Cable/switch/router; try static IP on W5x00 to isolate DHCP.
- **Blynk no updates**: Token + V-pins (V0/V1/…V5) + URL.
- **ThingSpeak no updates**: Write API Key + field mapping.
- **MQTT no publish**: AIO username/key in `settings.toml`, feed names, broker `io.adafruit.com`.
### 7. Future Content Directions
These four tutorials highlight that IRIV IO Controller can cover the full chain:
**sensor data acquisition → network transfer → cloud integration → automation control.**
The next steps of content we can expect include:
- **Security and Encryption**
Using TLS for MQTT, HTTPS data transfer, certificate management.
- **Edge AI Integration**
Running lightweight AI models on the controller for **predictive control**, not just monitoring.
- **Large-Scale IoT Platform Integration**
Connecting to AWS IoT Core, Azure IoT Hub, or Google Cloud IoT.
- **Expanded Industrial Applications**
Beyond agriculture: smart factories, building automation, energy management demos.
## Documents / Sources(Original Link)
- IRIV IO Controller IoT Gateway :[**Blynk**](https://my.cytron.io/tutorial/iriv-io-controller-iot-gateway-blynk)
- IRIV IO Controller IoT Gateway : [**ThingSpeak**](https://my.cytron.io/tutorial/iriv-io-controller-iot-gateway-thingspeak)
- IRIV IO Controller IoT Gateway : [**MQTT**](https://my.cytron.io/tutorial/iriv-io-controller-iot-gateway-mqtt)
- Sample Application: [**Agriculture Automation with IRIV**](https://my.cytron.io/tutorial/sample-application-automation-of-agriculture-with-iriv-io-controller)
---
Source: https://maker.wiznet.io/irina/projects/iriv-io-controller-series-rs-485-modbus--ethernet--cloud-blynk-thingspeak-mqtt-agricult/