Parallel I/O Card Boosts Output With CPLDs

The 4I24H is a 96-bit parallel I/O card implemented on the PC/104 bus. It uses CPLDs to emulate 82C55 parallel I/O chips but provides greater output current, it's claimed. The board can sink 24 mA from each output pin. CPLDs emulate all mode-0 82C55 oeprations. Pull-up resistors (3.3k) are provided on all I/O bits to simplify interfacing with contact closures, opto-isolators, and other devices. Two 50-pin headers are used for I/O connections and each header has 48 I/O bits, ground, and power. Pricing starts around $134 each/100.