Acromag AVME9471 Industrial Digital I/O Board

The Acromag AVME9471 is a VMEbus-resident digital I/O board that interfaces discrete devices with industrial VME-based computer systems. It delivers 80 total digital I/O points organized across four independent sections, each built around a Zilog Z8036 Counter/IO chip. Every section provides 20 programmable I/O points configurable as inputs or outputs, three counter/timers capable of generating square waves (15.26 Hz to 100 kHz) and one-shot pulses (500 nS to 32 mS), and comprehensive interrupt support with selectable priority and sensing modes.

A Logic Cell Array (LCA) manages the interface between the Z8036 and user application, with jumper-selectable programs that enable features such as programmable input debouncing (3 µS minimum to 0.2 seconds) and handshaking in interlocked, strobed, three-wire, or pulsed configurations. The board accepts counter/timer input frequencies up to 3.3 MHz with a minimum pulse width of 170 nS.

Technical Specifications

• Digital I/O Points: 80 total, individually configurable as inputs or outputs


• I/O Sections: 4 independent sections with 20 programmable points per section


• Core Processor: Zilog Z8036 Counter/IO chip per section


• Counter/Timers: 3 per section; square wave output 15.26 Hz to 100 kHz; one-shot pulse 500 nS to 32 mS


• Counter Input Frequency: Up to 3.3 MHz, minimum pulse width 170 nS


• Input Debounce: Programmable 3 µS minimum to 0.2 seconds


• Interrupt Levels: Support for I(1-7) request levels with programmable priority and sensing


• Handshaking Modes: Interlocked, strobed, three-wire, pulsed


• Input Voltage Range: 0 to 5 V DC


• Input Thresholds: 0.8 V DC (H to L), 2.0 V DC (L to H)


• Input Current: 20 µA @ 5 V DC


• Output Type: Open collector with pull-up resistor


• Output Current: 100 mA (8-bit ports), 60 mA (4-bit ports) maximum


• Output Saturation: 0.6 V max, 0.4 V typical @ 100 mA


• Power Supply: +5 V DC ±5%, 3.0 A maximum

Key Features

• Meets VMEbus specification revision C.1 (October 1985) and IEC 821-1987


• A24/A16:D16/D08 (EO) DTB slave and D08 (O) ROAK interrupter operations


• Address modifier codes: 29H, 2DH, 39H, 3DH


• Four 50-contact front panel connectors


• DIN 41612 160-pin Type C Level II VMEbus connectors (P1 & P2)

Compatibility & Integration The AVME9471 integrates into standard VMEbus backplanes and supports multiple addressing modes for flexible system architecture. Front panel connectors accommodate direct interface to industrial discrete control logic and sensor arrays.