Product Details

The XYCOM XVME-688, PN 74688-001, is a discontinued 6U double-high VMEbus PC/AT compatible processor module, paired with XVME-678 in the same product series, designed for XYCOM legacy VME automation racks and rugged embedded industrial measurement and control systems. It adopts Intel 80386SX processor running at 25MHz, with an onboard socket for optional 80387SX math coprocessor to support high-precision floating-point calculation tasks. It supports 1MB or 4MB DRAM configuration, adopting low-power CMOS design, stable for long-time continuous operation, and can run DOS, VRTX and other classic real-time operating systems widely used in old industrial control equipment.

This SBC integrates Super VGA graphics controller for local display output and on-site debugging. It carries IDE hard disk controller, floppy disk controller, two RS232 serial ports, one EPP/ECP parallel port and PS/2 keyboard interface. It reserves a PC/104 expansion site, which can install third-party PC/104 modules to add analog acquisition, digital I/O or communication functions. It conforms to IEEE 1014 VMEbus specification, can work as VME bus master and slave, supports A16/A24 addressing, complete 7-level VME interrupt and bus arbitration mechanism, and can access and control analog acquisition, digital I/O, counter and communication modules on the VME backplane. The module cannot access VME bus under protected mode, which needs to be noted during program development. It is equipped with hardware watchdog timer to realize automatic reset when software crashes, improving the reliability of unattended operation.

Users can configure VME base address, interrupt mapping and memory allocation through on-board jumpers and DIP switches to avoid resource conflicts with other VME modules. On-board power filtering and transient suppression circuits reduce electromagnetic interference from inverters, servo drives and contactors, ensuring stable operation in noisy factory and test environments. The front panel is equipped with LED indicators for power status, pass and fault signals, together with standard VGA, serial, parallel and keyboard connectors, helping maintenance technicians quickly judge boot status, bus error and runtime faults during commissioning and routine inspection. The PCB adopts industrial-grade electronic components and reliable EMC protection design, capable of resisting vibration, dust and temperature fluctuation in aerospace test benches, power plant monitoring systems, semiconductor test equipment and automated production lines. This legacy 386SX VME CPU board is mainly supplied as spare replacement parts for existing XYCOM VME automation systems. Users need to confirm firmware version, memory configuration and backplane definition before installation. A conformal coated version is optional for high humidity, dusty and corrosive industrial sites. This model is widely used in data acquisition hosts, batch test control, old PC-based VME control system retrofit projects.

This 386SX PC/AT VME single board computer adopts standard 6U double-high VME rack mount structure. It draws power from the VME backplane. LED indicators display power status, pass and fault status for convenient on-site inspection. The operating temperature range is 0°C to 65°C, storage temperature ranges from -40°C to +85°C, relative humidity 5% to 95% non-condensing. It complies with industrial shock, vibration and EMC standards and has CE certifications. It supports memory mapping and interrupt configuration backup for fast recovery after hardware replacement.

This XYCOM XVME-688 processor module is widely applied in legacy VME control racks and industrial automation upgrade projects. It serves as classic PC/AT compatible host to execute early industrial control software and coordinate VME backplane modules. As a reliable discontinued spare part, the XYCOM XVME-688 retains original VME bus timing and firmware compatibility, and effectively reduces the renovation cost of legacy industrial control system maintenance.