Industrial Universal PCI card with 24-channel Digital I/O. The PIO-D24U/D56U and PEX-D56/D24 cards are the new generation product that ICP DAS provides to meet RoHS compliance requirement and is designed as completely compatible with the PIO-D24/D56. Users can replace the PIO-D24/D56 by the PIO-D24U/D56U and PEX-D24/D56 directly without software/driver modification.The PIO-D24U/D56U supports 3.3 V/5 V PCI bus, while the PEX-D24/D56 supports PCI E..