Interface Technology IO100VXI 128-Channel TTL Digital I/O Module

The Interface Technology IO100VXI is a C-size, single-slot VXIbus module that delivers 128 TTL-compatible digital I/O channels for high-density test and control applications. The module supports multiple logic families—TTL, CMOS, TTL Open Collector, Differential TTL, and Switched HV Outputs—with software-configurable 8-channel groups operating as inputs or outputs. Four 50-pin IDC connectors provide 32 I/O channels per connector, plus handshake strobes and tri-state control lines. Tri-state output control enables emulation of bi-directional data and control buses, while user-configurable termination and mezzanine board support allow integration of custom I/O drivers. The module handles switched high-voltage outputs up to 100 V and supports external handshaking with defined channel-to-channel skew plus 50 ns inter-card skew.

## Technical Specifications

• **Channel Configuration:** 128 digital I/O channels; 8-channel groups independently configured as input or output
• **Connectors:** Four 50-pin IDC connectors; 32 I/O channels, 4 handshake strobes, and 4 tri-state control inputs per connector
• **Logic Families:** TTL, CMOS, TTL Open Collector, Differential TTL, Switched HV Outputs
• **Differential I/O:** RS-422-A standard compliance
• **Data Fields:** User-defined widths from 1 bit to 32 bits
• **High-Voltage Capability:** Switched outputs to 100 V; selectable from +5V, ±12V, ±24V via VXI backplane
• **Handshake Lines:** Byte Available, Byte Request, Data Valid, Data Acknowledge per connector
• **Tri-State Control:** 4 lines per I/O connector for output enable and bi-directional bus emulation
• **VXI Power Consumption:** +5V: 20 W (P1) / 35 W (P2); +12V: 12 W; -12V: 12 W; +24V: 24 W; -24V: 24 W
• **Airflow Requirement:** Per-slot average 6 H₂O mm

## Key Features

• Software-programmable 8-channel groups for flexible I/O direction control
• User-configurable I/O termination
• Mezzanine board space for custom I/O driver integration
• VME dual-ported RAM and register access for setup and direct I/O control
• SCPI message-based commands and VXI memory-mapped register interface
• Synchronous multi-module triggering with TTL trigger expansion support
• External handshaking capability

## Typical Applications

• Automated test equipment (ATE)
• Data acquisition systems
• Industrial process control
• Microprocessor cycle emulation
• Bus cycle emulation
• Process simulation

## Compatibility & Integration

The IO100VXI integrates into standard VXI systems via single-slot C-size form factor. VME-based command and data transfer enable seamless integration with test frameworks supporting SCPI protocols and memory-mapped register access.