Product Overview

The XYCOM XVME-674 is a single-slot 6U VMEbus PC/AT-compatible processor module designed for industrial computer and embedded control applications.

Rather than being a conventional analog or digital I/O card, the XVME-674 functions as a complete VMEbus processor board. Historical Xycom documentation identifies versions using either a 33 MHz Intel 80486DX or a 66 MHz 80486DX2 processor, with 4, 16, or 32 MB of DRAM. The board also integrates IDE hard-disk and floppy-disk controllers, VGA graphics, two serial ports, and one parallel port.

The board combines PC/AT computing functions with a 32-bit VMEbus master/slave interface, making it suitable for legacy VME-based industrial computers and control systems.

Technical Specifications

The published XVME-674 datasheet specifically lists the 80486 processor options, three DRAM configurations, IDE and floppy controllers, VGA graphics, two serial ports, and one parallel port.

Main Features

The XVME-674 was designed for applications where a PC-compatible processor needed to operate directly within a VMEbus system.

Its main functions include:

• 32-bit VMEbus master and slave operation
• PC/AT-compatible computing environment
• On-board DRAM
• IDE hard-disk interface
• Floppy-disk controller
• VGA graphics support
• Two serial communication ports
• Parallel port
• VMEbus interrupt handling
• Programmable byte-swapping support
• PC/104 expansion capability

The XVME-674 and related Xycom processor boards were supported by Xycom’s MS-DOS software library, including routines for VMEbus memory access, interrupts, and other low-level board functions.

Typical Applications

The XVME-674 can be found in older VME-based industrial computer architectures, including:

• Industrial control computers
• Factory automation equipment
• Data acquisition systems
• Test and measurement equipment
• Motion and machine control
• Process control systems
• Legacy VMEbus computer platforms
• Embedded industrial computing
• Military and laboratory equipment using legacy VME architectures

For replacement applications, the important consideration is not only the physical 6U VME format but also the processor configuration, memory capacity, software environment, VME address configuration, and connected peripheral hardware.

Installation & Configuration

Before installation, verify the board model and hardware configuration from the physical label and PCB markings.

Recommended checks include:

1. Confirm XVME-674 identification and board revision.
2. Check the installed processor type and memory configuration.
3. Inspect the VMEbus connectors for bent, damaged, or oxidized contacts.
4. Verify jumper and switch settings against the original system configuration.
5. Confirm the VMEbus slot assignment.
6. Check IDE, floppy, serial, and parallel connections where used.
7. Verify VMEbus master/slave configuration.
8. Confirm the installed operating environment and application software.
9. Perform a controlled power-up and board diagnostic check.

Because this is legacy VME computer hardware, configuration details can vary by board revision and installed options. Avoid assuming that two XVME-674 boards have identical memory or processor configurations simply because they share the same base model.

Inspection & Maintenance

For a replacement or spare board, inspect the following before installation:

• PCB condition
• VMEbus backplane connectors
• Processor and socket area
• DRAM configuration
• Battery and RTC area, if fitted
• IDE and floppy connectors
• Serial and parallel connectors
• Jumpers and configuration switches
• Signs of corrosion or previous component repair

For long-term storage, keep the board in an ESD-safe bag and a dry environment. If the board is being returned to service after extended storage, a controlled power-up and functional test are recommended before connecting it to a production VME system.

Compatibility Notes

The XVME-674 is a processor module, not a general-purpose VME analog/digital I/O board.

Related Xycom processor models such as XVME-677, XVME-678, and XVME-688 exist, but they use different processors and hardware configurations. They should therefore be treated as related products rather than automatic replacements. Xycom’s software documentation separately identifies the XVME-674 as one of the supported PC/AT processor modules.

When replacing an installed unit, compare:

• Exact model
• Board revision
• CPU type
• DRAM capacity
• Jumper/switch configuration
• VMEbus settings
• Peripheral interfaces
• Operating system and application requirements

Condition

eBay-listed condition: Used. The supplied eBay listing identifies the unit as Used and lists the model as XVME-674/XVME674. The listing’s MPN field shows XVME-085, so the physical nameplate should be checked carefully before shipment.

Actual cosmetic condition, labels, connectors, and included accessories should be judged from the physical unit and listing photographs.

Ordering Information

Please confirm the following when ordering:

• Model: XVME-674
• Processor version, if important to your application
• Installed memory capacity
• Board revision
• Required quantity
• Existing VME system or controller information

For a direct replacement, providing a photograph of the existing board label and front/rear connectors is the safest way to verify the configuration.

Recommended eBay Title

XYCOM XVME-674 | 6U VMEbus 80486 Processor Module | Industrial Computer Board