Abaco Systems / VMIC VMIVME-2528-000 128-bit TTL Digital Input/Output Board

The Abaco Systems VMIVME-2528-000 is a 128-bit TTL Digital Input/Output board engineered for VMEbus systems requiring high-density signal interfacing. This double Eurocard (6U) module delivers 128 individually configurable I/O channels with 8-bit and 16-bit data transfer capability, supporting both control and real-time monitoring in industrial automation environments. The board features 24 mA output sink capability per channel, positive or negative true data logic options, and real-time loopback functionality for signal verification.

All outputs initialize in tristate mode via master clear, with automatic release upon the first write transfer to any port.

Technical Specifications

• Channels: 128 Input/Output


• Data Transfer: 8-bit and 16-bit transfers


• Form Factor: VME Double Eurocard (6U)


• I/O Standard: TTL compatible


• Output Sink Current: 24 mA per channel


• Output Logic: Positive or negative true data I/O selectable


• Power-up State: Tristate initialization via master clear; automatic release on first write


• Addressing: Addressable within short supervisory or short non-privileged I/O space; sixteen ports individually addressable on 8- or 16-bit boundaries


• Address Configuration: Twelve DIP switches enabling unlimited short data I/O address map selection


• I/O Connector: 64-pin DIN 41612


• Operating Temperature: 0 to 55 °C


• Storage Temperature: −20 to 85 °C

Key Features

• Individual port direction control via jumpers


• Alternating ground pins on I/O connector for signal integrity


• Real-time loopback capability for diagnostics


• Non-privileged and supervisory short I/O transfer support


• Flexible addressing within VMEbus I/O address space

VMEbus Compatibility & Integration Fully compliant with VMEbus specification (ANSI/IEEE STD 1014-1987, IEC 821 and 297) with A16:D16 mnemonics. Supports A24:A16:D32/D16/D08 (EO) slave configurations in 6U form factor. Integrates directly into standard VMEbus backplanes supporting 39/3D:29/2D address decoding.