4 Ports RS232 x2 (Com1 & Com2 ) RS422/RS485 x2 (Com3 & Com4 ). DB9 RS232 serial ports, (Com1 & Com2 ) &. COM1 & COM2 RS232, COM3 & COM4 RS422/RS485. Compliant with PCI Local Bus Specification 2.3. two DB9 RS422/RS485 serial ports (Com3 & Com4).
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