MOTOROLA MVME705A Serial Transition Module

MOTOROLA MVME705A Serial Transition Module

Features:

Single- or Double-Slot VME Transition Card

Integrated Circuit Logic

Three DB-25 Ports

The Motorola MVME705 6-Channel Serial Transition Module supports two synchronous I/O ports for the MVME333-2 XCC card. 

SP1 connects the Application Module Link (AML) to the Meridian 1. 

This module features Integrated Circuit Logic with potentially replaceable circuit chips, as well as three DB-25 interfaces.

torola MVME705A 6-Channel Serial Transition Module Specs

General

Manufacturer Emerson / Motorola

Model MVME705A

Product Family MVME705B, MVME 705B, VME705B, VME 705B, VME-705B, MVME-705-B, VME-705-B, MVME705, 

MVME 705, VME705, VME 705, VME-705, MVME705A, MVME 705 A, MVME 705A

Introduction

The MOTOROLA MVME705A is a specialized Rear Transition Module (RTM) designed for the VMEbus architecture.

It serves as the physical interface layer for the MVME332XT series of Intelligent Communication Controllers.

The MVME705A is engineered to route high-density serial signals from the internal VME backplane to standard external connectors, 

enabling reliable data communication between the VME processor and peripheral industrial devices.

Technical Parameter Table

Related Models

MVME705B: The updated version with slightly different grounding or IC revisions.

MVME332XT: The primary Intelligent Communication Controller card paired with this RTM.

MVME712A: A transition module often used for SCSI and synchronous serial data.

MVME707: A specialized transition module for serial and parallel I/O.

Application Cases

Industrial SCADA Systems: Acting as a gateway to connect multiple PLCs (Programmable Logic Controllers) to a central VME-based management server.

Legacy Telecom Infrastructure: Used in large-scale switching systems (like the Northern Telecom Meridian 1) for AML (Application Module Link) communications.

Power Grid Monitoring: Interfacing with remote terminal units (RTUs) via RS-232/RS-422 protocols for real-time grid telemetry.

Traffic Control Systems: Managing multi-channel sensor data from roadside units in municipal transit networks.

Product Advantages and Features

Multi-Channel Efficiency: Consolidates six independent serial channels into a compact 6U footprint, maximizing rack space.

Rear-Access Design: Allows for "Clean Front" maintenance; technicians can swap CPU boards from the front without disturbing the fixed I/O wiring at the rear.

Signal Integrity: Features high-quality filtering and shielding to minimize EMI (Electromagnetic Interference) in noisy factory environments.

High Compatibility: Specifically tuned for the MVME332XT, ensuring zero-latency signal passthrough and full support for asynchronous communication.

Other Models in the Same Series

MVME701 (Basic Interface Board)

MVME705 (Standard 6-Channel Base Model)

MVME712M (Multi-interface: SCSI/Serial/Ethernet)

MVME715P (Printer/Peripheral Interface Card)

Installation and Maintenance

Installation: The MVME705A must be installed in the rear of the VME chassis, aligned exactly with the P2 connector of the host controller card (e.g., MVME332XT). Ensure the power is off before seating the module to prevent arcing.

Maintenance: This is a passive-logic board with no user-serviceable software. 

Maintenance involves periodic visual inspection of the DB-25 pins for oxidation and ensuring the captive screws remain tight to resist vibration.

ESD Caution: Always use an anti-static wrist strap when handling the board, as the CMOS components are sensitive to electrostatic discharge.

Unique Product Description

The MOTOROLA MVME705A is a cornerstone of legacy VMEbus reliability.

While modern systems have moved toward USB and Ethernet, 

the MVME705A remains an indispensable component for industries where synchronous and asynchronous serial communication is non-negotiable.

Its robust construction and "fit-and-forget" reliability make it the preferred choice for maintaining mission-critical infrastructure in power plants, refineries, and telecommunication hubs worldwide.