EAU-321 Multi Protocol Serial Port Card

EAU-321 Serial Port Board Integration Guide

In fire alarm and life safety systems, data exchange with third-party devices is one of the most common and challenging tasks in system integration. The Autronica AutoSafe system, as a mature fire alarm control platform, provides a dedicated internal communication protocol AutoCom. However, to interface the system with building management systems, paging systems, or external PLC devices, hardware level protocol conversion and physical interface support are required. The EAU-321 four channel multi protocol serial communication board was born for this purpose - it is a PC/104 specification expansion module that can be installed inside the AutoSafe system unit, providing RS232, RS422, or RS485 interfaces through flexible jumper settings to achieve reliable data exchange with external devices.

This article will provide a detailed interpretation of the technical features, port allocation strategy, jumper configuration method, installation steps, and common application scenarios of EAU-321 from an engineering practice perspective, helping system integration engineers and on-site maintenance personnel quickly grasp the key points of using this module.

Product positioning and core features

EAU-321 is a four channel serial communication board that follows the PC/104 bus standard. Its design goal is very clear: to occupy a small amount of space inside the AutoSafe system unit (fire alarm control panel BS-310/320 or controller BC-320) and provide flexible multi protocol serial port expansion capability.

List of Core Features

Four channel independent serial port: supports simultaneous connection of up to four external devices

Multi protocol support: Ports 1 and 2 can be switched between RS232, RS422, and RS485 through jumper settings; Ports 3 and 4 are fixed RS232 ports

AutoCom redundant communication: Ports 1 and 2 support redundant AutoCom communication, improving the availability of critical links

Special function allocation: Port 3 is reserved for AutoSafe IFG AutoFieldBus communication, and Port 4 is used for downloading AUTROLON network configuration

Compact PC/104 size: 90 × 96mm, can be directly stacked on EAU-310 communication board or EAC300 processor board

Wide temperature range: -40 ° C to+85 ° C, suitable for industrial environments

Short circuit protection: All outputs have continuous short circuit protection capability

These features make EAU-321 not only suitable for standard fire alarm system integration, but also capable of handling industries such as ships, oil and gas that require higher reliability and environmental adaptability.

Detailed explanation of port functions

Understanding the allocation and electrical definition of each port is the first step towards successful integration. The four ports of EAU-321 are not completely equivalent, as they undertake different system responsibilities.

Ports 1 and 2- Multi protocol AutoCom ports

Ports 1 and 2 are the "flexible interfaces" of the system, with the most extensive uses:

Supports three electrical standards: RS232, RS422, and RS485 (selected through jumper)

Mainly used for AutoCom communication, i.e. standard protocol transmission between AutoSafe system and third-party devices

Redundant communication configuration can be achieved: two ports are simultaneously connected to the same third-party device, and when one link fails, it automatically switches, significantly improving the system's fault tolerance capability

In practical engineering, ports 1 and 2 are often configured in the following modes:

RS232 mode: Short distance (<15 meters) point-to-point connection, suitable for old-fashioned serial devices or debugging interfaces

RS422 mode: Long distance (up to 1200 meters) point to multipoint, four wire full duplex, suitable for communication with remote devices such as building management systems

RS485 mode: Long distance multi-point half duplex, supporting up to 32 nodes, commonly used for Modbus RTU bus

Port 3- AutoFieldBus dedicated port

Port 3 is a fixed RS232 interface specifically assigned for AutoSafe IFG AutoFieldBus communication. AutoFieldBus is a bus protocol used within the AutoSafe system to connect field devices such as detectors and input/output modules. The existence of Port 3 allows engineers to diagnose, configure, or collect data directly from the fieldbus through the serial port without going through the main processor.

This port does not support changing the protocol type through jumper cables and always uses RS232. If communication with RS422/485 devices is required, port 1 or 2 should be used in conjunction with an external converter.

Port 4- AUTROLON download port

Port 4 is also a fixed RS232 interface, and its special purpose is for downloading AUTROLON network configuration files. In a distributed system, multiple fire alarm control panels are interconnected through the AUTROLON network. System configurations (such as device databases, logic equations, and linkage schemes) are usually distributed uniformly from the "booting panel". Engineers can download the complete configuration file to the startup panel by connecting port 4 to the configuration computer, and then the startup panel automatically synchronizes to all other panels through the AUTROLON network.