NI AT-DIO-32HS High-Speed Digital I/O Board

The NI AT-DIO-32HS is a high-speed digital I/O board for PCI systems delivering 32 channels of TTL/CMOS-compatible input and output. Organized into four 8-bit ports, channels group flexibly into two 8-bit, two 16-bit, or single 32-bit configurations to support pattern I/O, handshaking, and unstrobed modes. The board reaches transfer rates up to 20 MHz (80 Mbytes/s for 32-bit transfers) and pattern I/O speeds to 2 MHz, making it suitable for industrial automation, laboratory test systems, and enterprise data acquisition requiring synchronized, high-performance digital control.

– Technical Specifications

Digital I/O Architecture
• 32 channels organized into four 8-bit ports
• Flexible grouping: two 8-bit groups, two 16-bit groups, or one 32-bit group
• 5 V TTL/CMOS compatible signaling

Transfer Performance
• Maximum transfer rate: up to 20 MHz (80 Mbytes/s for 32-bit transfers)
• Pattern I/O speed: up to 2 MHz

Electrical Characteristics
• Input logic levels: 0 V to 0.8 V (low); 2 V to 5 V (high)
• Output drive current: ±24 mA per line
• Input hysteresis: 500 mV
• Absolute maximum input voltage: -0.3 V to 5 V
• Data line input current: -70 µA to 40 µA (depending on pull configuration and voltage level)
• Control line input current: -2.5 mA to 1.4 mA (depending on pull configuration and voltage level)
• Pull-up/down resistors: 100 kΩ (data lines), 2.2 kΩ (control lines)
• Input termination: diode termination to suppress line reflections

Interfaces & Connectivity
• PCI bus interface (32-bit, 5 V)
• 68-pin SCSI-II male connector for digital signals
• Start/stop triggering, pattern detection, and change detection
• RTSI bus and PXI trigger bus support for clock and trigger synchronization

– Key Features

• Diode-terminated inputs minimize signal reflections on long cable runs
• Selectable pull-up or pull-down on data and control lines at power-on
• Multiple operational modes: pattern I/O, handshaking, unstrobed I/O
• DMA and interrupt-driven data transfer support

– Typical Applications

• Industrial process control and automation
• Laboratory test and measurement systems
• Sensor and actuator interfacing
• High-speed pattern generation and detection

– Compatibility & Integration

The board integrates with National Instruments DAQ software through the PCI interface and synchronizes with external systems via RTSI or PXI trigger buses. Related products include the AT-DIO-32F and PCI-DIO-32HS/PCI-6533.