Product Overview

Introduction

The E840-TTL (EC05-xxx) series is a compact, high-performance 4G CAT1 pin module designed for rapid IoT device integration. Measuring just 25×25 mm, this module enables bidirectional transparent data transmission between serial devices and network servers with minimal configuration. The 2.0mm pin header design simplifies integration into existing IoT projects, supporting both standard industrial voltage ranges and multiple network protocols.

With native support for MQTT, HTTP, TCP, and UDP protocols, the module seamlessly connects to major cloud platforms including Alibaba Cloud, OneNET, Baidu Cloud, and Huawei Cloud, making it suitable for a wide range of IoT applications from industrial monitoring to smart city infrastructure.

Key Features

• 4G CAT1 technology with millisecond-level latency for real-time data transmission

• Multi-region frequency support for global deployment

• Transparent data transmission between serial port and network without protocol conversion

• Dual independent socket connections with master/slave configuration options

• Native MQTT 3.1.1 support for all major IoT cloud platforms

• Automatic Modbus RTU to TCP conversion for industrial automation applications

• Quick AT command support via serial, network, or SMS (model-dependent)

• Configurable heartbeat and registration packets for connection stability

• Multi-link protocol distribution for targeted data routing

• Dual power input support: 4.5~18V DC or 3.3~4.3V lithium battery

• Optional GNSS positioning (GPS/BeiDou/Galileo/GLONASS) on DGC model

• AWS certificate support on DNE-V2 model for enhanced security

• Wide operating temperature range (-40°C to +85°C) for industrial environments

System Parameters

Indicator Lights

Pin Definitions

Quick Start Guide

Hardware Preparation

Before starting, gather the following components:

• E840-TTL (EC05-xxx) module

• 12V DC power supply (minimum 2A output)

• Nano SIM card (activated, with data plan)

• USB to TTL converter (3.3V level)

• 4G LTE suction cup antenna with IPEX to SMA adapter

• Jumper wires for connections

• (Optional) GNSS active antenna for DGC model, installed outdoors with clear sky view

Parameter Configuration

The module comes pre-configured to connect to Ebyte's test server by default. For testing basic functionality, you may skip this section. For connecting to your own server, follow these steps:

Communication Testing

Advanced Function Configuration

Data Pass-Through Mode

In data pass-through mode, the module transparently transmits data between the serial port and network server without requiring protocol conversion from the host device. Two independent socket links are supported, each configurable as TCP Client, UDP Client, TCP Server, or UDP Server (TCP/UDP Server modes require APN card support).

Heartbeat Packets

Heartbeat packets maintain connection stability during periods of inactivity, preventing server disconnection. Two types are supported:

• Network Heartbeat: Sent to the server at configured intervals, configurable content includes ICCID, IMEI, SN, GPS (DGC only), or custom data (up to 64 bytes ASCII / 32 bytes HEX). Supports TCPC, MQTTC, and HTTPC modes only.

• Serial Heartbeat: Sent to the serial port at configured intervals for polling serial devices, with customizable data content.

 Registration Packets

Registration packets allow the server to identify connecting devices. They can be sent once when the connection is established, or appended as a header to every data packet. Content options include ICCID, IMEI, or custom data.

 Multi-Link Protocol Distribution

When enabled, this feature allows routing serial data to specific socket links using special packet headers, and adds identifying headers to data received from different links. Example configuration with two sockets:

• Socket 1 (Port 8887): Data with header "55 FE AA 00" is routed to this link

• Socket 2 (Port 8888): Data with header "55 FE AA 01" is routed to this link

• Unidentified data is sent to both links

• Received data from Socket 1 gets header "AA FE 55 00" added before serial transmission

• Received data from Socket 2 gets header "AA FE 55 01" added before serial transmission

Short Connection Mode

For TCPC mode, short connection mode closes the server connection after a configured period of inactivity, reducing power consumption for battery-powered applications. The connection automatically re-establishes when new data needs to be sent. Configurable timeout up to 65535 seconds.

MQTT Mode

The module natively supports MQTT 3.1.1 protocol with pre-configured profiles for all major IoT cloud platforms, eliminating the need for host-side MQTT protocol implementation. Three subscription and publishing topics are supported for flexible data routing.

Alibaba Cloud MQTT Connection

1. Log in to Alibaba Cloud IoT Platform and create a product and device instance

2. Obtain the three connection elements: ProductKey, DeviceName, and DeviceSecret

3. In the configuration software, set connection type to "MQTT Client" and MQTT target platform to "Alibaba Cloud"

4. Enter the ProductKey, DeviceName, and DeviceSecret in the corresponding fields

5. Configure publish and subscribe topics as required by your application

6. Save configuration and restart the module

Baidu Cloud MQTT Connection

1. Log in to Baidu IoT Core and create a product and device

2. Obtain the device connection parameters: endpoint, username, and password

3. In configuration software, set MQTT target platform to "Baidu Cloud"

4. Enter the connection parameters and configure topics

5. Create a message template and rule engine in Baidu Cloud console for data backhaul

6. Save configuration and test communication

OneNET Cloud MQTT Connection

1. Log in to China Mobile OneNET platform and create an MQTT product

2. Add a device and record the Product ID, Device ID, and authentication key

3. In configuration software, set MQTT target platform to "ONENET Cloud"

4. Enter the Product ID, Device ID, and authentication key

5. Configure publish and subscribe topics (OneNET automatically generates topics with publish/subscribe attributes)

6. Save configuration and test data transmission

Huawei Cloud MQTT Connection

1. Log in to Huawei Cloud IoT Device Access service and create a product and device

2. Record the Device ID and DeviceSecret

3. Use Huawei's MQTT Client ID generator to calculate the connection parameters (Client ID, Username, Password)

4. In configuration software, set MQTT target platform to "Huawei Cloud"

5. Enter the generated connection parameters and configure topics

6. Save configuration and restart the module

Standard MQTT 3.1.1 Connection

For any standard MQTT 3.1.1 broker (including self-hosted servers):

1. Set MQTT target platform to "Standard MQTT 3.1.1"

2. Enter the broker address, port (typically 1883 for unencrypted, 8883 for TLS)

3. Enter Client ID, Username, and Password as required by your broker

4. Configure publish and subscribe topics with appropriate QoS levels (0, 1, or 2)

5. Save configuration and test connection

HTTP Mode

The module supports HTTP client functionality for direct interaction with web services and REST APIs, supporting both GET and POST methods.

GET Request Configuration

1. Set connection type to "HTTP Client"

2. Enter the server address and port (typically 80 for HTTP, 443 for HTTPS)

3. Set HTTP transmission method to "GET"

4. Enter the URL path and any required headers (authentication, content type, etc.)

5. Configure whether to return response headers with the data

6. Save configuration. Data sent via serial port will trigger an HTTP GET request, with the response returned via serial port.

POST Request Configuration

1. Set connection type to "HTTP Client"

2. Enter the server address and port

3. Set HTTP transmission method to "POST"

4. Enter the URL path and headers (including Content-Type for the POST body)

5. Save configuration. Data sent via serial port will be sent as the POST body, with the server response returned via serial port.

SMS Pass-Through Mode

Supported on select models, this mode enables SMS communication via the serial port:

• Data received on the serial port is sent as SMS to the configured target phone number

• SMS received by the module is transparently transmitted to the serial port

• Optional phone number filtering to only accept SMS from specified numbers

Security Configuration

To prevent unauthorized configuration, the module supports password protection for configuration mode:

1. Enable "Security Configuration" in the advanced settings

2. Set a 0-32 byte configuration password

3. Save configuration and restart

4. When entering configuration mode, send "+++" followed by "AT+PASSWORDSET=[your password]" within 30 seconds to gain access 

Quick AT Commands

When enabled, quick AT commands allow configuration changes directly via serial port, network, or SMS without entering command mode with "+++". Commands must be prefixed with the configured security password, e.g., "NETAT*AT+VER" to query firmware version if the password is "NETAT*".

Modbus TCP to RTU Conversion

The module automatically handles conversion between Modbus RTU (serial) and Modbus TCP (network) protocols for industrial automation applications:

1. Enable "Modbus RTU/TCP Conversion" in the configuration

2. Set the conversion address (0 to convert all addresses, or specific address for targeted conversion)

3. Save configuration. The module will automatically convert Modbus RTU queries from the serial port to Modbus TCP for the network, and vice versa for responses.

Additional Features

• APN Configuration: Custom APN settings for specialized network operators, configurable via AT commands

• Serial Port Upgrade: Firmware updates via the serial port using Ebyte's flashing tool

• Hardware Factory Reset: Pull RELOAD pin low for 5-6 seconds during power-on to restore all default parameters

• Serial Port Framing: Configurable packetization time (0-1024ms) and packet length (50-1024 bytes) for optimized serial data handling

• NTP Time Acquisition: Query network time via AT+NTP command, returning timestamp in format "YYYY.MM.DD, HH:MM:SS"

• IP Address Query: Obtain module's current IP address via AT+IP command

• No-Data Restart: Automatic module restart if no downlink data is received for the configured period (30-65535 minutes), ensuring continuous operation

Application Examples

The E840-TTL (EC05-xxx) series is suitable for a wide range of IoT applications:

• Industrial Remote Monitoring: Connect PLCs, sensors, and industrial controllers to cloud platforms for real-time monitoring and control

• Smart Metering: Enable remote reading of electricity, water, and gas meters with automatic data upload

• Smart Agriculture: Monitor environmental conditions (temperature, humidity, soil moisture) in greenhouses and fields

• Smart City: Connect streetlights, parking sensors, and waste management systems for city-wide monitoring

• Asset Tracking: Use the DGC model with GNSS for real-time location tracking of vehicles, containers, and mobile assets

• Retail Automation: Connect point-of-sale systems, vending machines, and digital signage for remote management

• Healthcare: Enable remote patient monitoring devices and medical equipment connectivity

Troubleshooting