Advantech BB-485PTBR Converter, RS-232 to RS-485, Female DB9 connector with pins 2(RD), 3(TD), and 5(SG) supported, 8-Position Pluggable Terminal Block Connector $101.40 Select
Advantech BB-4WSD9R Serial Converter, RS-232 DB9 F to RS-422/485 DB9 F, Port Power Ability $95.00 Select