QUATECH's single port SSCLP-200/300 and dual port DSCLP-200/300 universal PCI serial cards, available from Interworld Electronics, provide support for RS422/485 full duplex and RS485 half duplex operation with auto-toggle RS485 driver control and are compatible with 5V and 3.3V PCI and PCI-X slots.
This may not be a problem as most computers have more than one PCI-X bus and any true PCI-X cards can be installed in a separate bus. At this point in time there are no 64-bit 133MHz serial cards for the PCI-X bus and using a Quatech Universal PCI card may be your only option. Quatech's Universal PCI cards support baud rates up to 460.8kbps, share a single PCI interrupt and provide Windows 95/98/Me/NT/2000/XP and OS/2 driver support.
Quatech's universal PCI cards also have a low profile form factor making them ideal for installation in 2U rack mount industrial chassis.
Source: Quatech
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