The Tektronix VX4801 is a 48-channel optically isolated digital I/O module for VXIbus systems. It provides message-based VXI communication (Rev 1.4) with independently configurable 8-bit byte channels, supporting both TTL and CMOS logic levels. Each output delivers up to 24 mA sink current. The module features programmable input/output sense (active high or low), user-defined masking, external handshake control, and built-in self-test electronics. Front panel indicators monitor power supply, fan operation, and internal temperature status. A dual-speed fan maintains thermal management. The VX4801 integrates into approved VXIbus mainframes with Slot 0 controller and system controller support, enabling automated test environments where multi-device communication and isolated digital control are essential.
Technical Specifications
• Digital I/O Channels: 48 optically isolated lines
• Channel Organization: Six independent 8-bit bytes
• Logic Levels: TTL and CMOS compatible
• Output Drive: 24 mA sink current per line
• Programmable Sense: Active high or active low configuration
• Masking: User-defined programmable masks supported
• Handshake Control: External handshake control signals
• Self-Test: Built-in test electronics (BITE)
• VXI Interface: Message-based; VXI Rev 1.4
• Firmware: Rev 1.5
• Hardware: Rev 671-3439-01
• Manufacturer ID: BFFC
• Device ID: F4DE
• Connectors: DB-50 male for digital I/O
• Dimensions: 12 × 10 × 8 inches
• Weight: 5.3 lbs
• Cooling: Two-speed fan
– Key Features
• Optical isolation across all 48 I/O lines for noise immunity and system protection
• Independent byte-level configuration enables flexible signal routing
• Programmable polarity and masking support custom handshake protocols
• Front panel status indicators for real-time system monitoring
• Diagnostic self-test for field verification and troubleshooting
– Typical Applications
• Automated test and measurement systems requiring isolated digital control
• Multi-instrument VXIbus environments with mixed TTL/CMOS signal requirements
• Applications demanding external handshake synchronization and protocol flexibility
– Compatibility & Integration
The VX4801 installs in approved VXIbus mainframes equipped with a Slot 0 controller (such as the VX4521 Resource Manager) and a system controller running National Instruments NI-488.2M software. It integrates with other Tektronix VXIbus modules within the same chassis architecture.
