The Keithley/MetraByte PIO-12 is a 24-line parallel digital I/O interface board for IBM PC and compatible systems. It provides configurable TTL/CMOS-compatible input and output channels via three 8-bit ports, with interrupt capability and flexible address decoding for industrial automation, laboratory research, and educational applications.
## Technical Specifications
• **Digital I/O Channels:** 24 lines across three ports
• **Port Configuration:** Port A and Port B are byte-wide (8 bits each), independently configurable as inputs or outputs. Port C is byte-wide and partitionable into Port C Lower and Port C Upper (4 bits each), each independently configurable as input or output
• **Logic Levels:** TTL/CMOS-compatible with input logic low -0.5V to 0.8V and input logic high 2.0V to 5.0V
• **Sink Current:** 1.7 mA
• **Source Current:** –200 µA
• **Bus Interface:** ISA slot
• **Address Decoding:** 10-bit I/O address decode; uses four consecutive I/O addresses
• **Interrupt Support:** Six interrupt levels available on PC bus with active-low enable line
• **Power Requirements:** ±5V, ±12V from computer supply; +5VDC @ 1.6A typical
• **Operating Temperature:** 0 to 50°C (32 to 122°F)
• **Storage Temperature:** 0 to 70°C (32 to 158°F)
• **Humidity:** 20 to 90% non-condensing
## Key Features
• 37-pin D-type connector
• CMOS pull-up capability via external 10kΩ resistor to +5V
• Compact form factor: 13.2 in L × 4.25 in H × 0.75 in D (335mm × 108mm × 19mm)
## Typical Applications
Industrial automation, laboratory instrumentation, real-time device monitoring and control, educational embedded systems development.
## Compatibility & Integration
Compatible with IBM PC/XT, PC AT, and compatible computers. Supports DriverLINX software framework with LabVIEW, TestPoint, VisualSCOPE, and ExceLINX drivers. Accessory panels include screw-terminal connectors (STC-37), electromechanical relay boards (ERB-24, ERA-01), and ribbon cable assemblies (C-1800).
