Logo RS485 Authority
Questions? Custom builds? We build and support all of our boards.
If you have a special application, we may already have a solution for you.
Give Ron a Call at 513-874-4796 or 513-638-0228 for additional information.
RSCOM2A: Async RS232 ↔ RS485 ↔ RS232 ↔ RS422 fast
automatic converter with removable connectors and LED indicators


RSCOM2A with Box


"Let me spin a very large
RS485 network for you!"

  • Fast auto TX-enable RS485 (2-wire, half-duplex) or RS485/RS422 (4-wire, full-duplex, fixed enable or auto TX-enable) for multi-drop, and/or point-to-point networks

  • Fast auto TX-enable RS232 ↔ RS485 interface converter for 2-wire, half-duplex communications, or fixed/auto TX-enable RS232 ↔ RS485/RS422 interface converter for 4-wire, full-duplex, point-to-point or multi-drop communications, at distances up to 4000 ft. and data rates up to 115.2Kbps

General Description:

The RSCOM2A is a fast Async bi-directional RS232 ↔ RS485 interface converter for 2-wire, half-duplex applications, with an automatic TX enable circuit, that will operate at data rates up to 115.2Kbps. The unit can also be used in 4-wire RS485/RS422 application (point-to-point or multi-drop, full-duplex). The unit has jumpers for bias, termination, RS232 DTE/DCE selection, and operating mode settings. The unit has edge mounted LED indicators, a removable screw terminal connector, and uses SN75LBC184P limited slew rate transceivers (1/2 unit load) with built-in transient protection.

The RSCOM2A is designed for office and/or industrial applications (non-isolated), and provides superior characteristics/features normally found only on more expensive units.

Need something special? Please contact us. We have additional isolated and non-isolated converters, repeaters, and repeater hubs. Units are generally stock to 2-3 business days for shipment. We design and manufacturer our entire product line, and offer technical support for our units, and can offer system recommendations for your application. Please give us a call: 513-874-4796

Related Files:

pdf icon
Converter Schematic and Physical Rev A

Physical Properties and Features:

RS232: 3-wire interface to RJ11/12 Connector (TX, RX, Common)
RS485: Removable screw terminal (Common, TX/RX-, TX/RX+, RX-, RX+, Common)
Power: 2.1mm center positive "Barrel" connector (9VDC)and Wago terminals
LEDs Power(YEL), TX-RS485(RED), RX-RS485(GRN), TX-RS232(RED), and RX-RS232(GRN)
Bias: 620 Ohm pull-up and pull-down (jumper selectable)
Termination: 120 Ohm or 240 Ohm (jumper selectable)
Special: Switching regulator for 9-35VDC operation
Protection: Up to 400W typical per SN75LBC184P specification


Distance: RS485/RS422 up to 4000 ft. (1250 meters)
Operation: 2-wire, half-duplex RS485 or 4-wire, full-duplex RS485/RS422
Format: Asynchronous with any combination of data bits, parity and stop
Speed: Up to 115.2Kbps (slew limited driver)
Temperarure:   0-65C (32-150F) ambient
Humidity: 10-90% non-condensing
Voltage: 9-35VDC
Power: Under 1/2 Watt (typical) + external load
Size: 3.50" X 3.00" X 0.9" (PC Board), with connectors: 3.50" X 3.25"
Mounting: 4-Holes 3.00" X 2.25" (built-in standoffs for #6 hardware)

Options and Ordering Information:

RSCOM2A: $89.00 ea. (Circuit board only)
Enclosure: $10.00 ea. (Medium)
Cable: $7.50 ea. (RS232, 7 ft., Specify DB9F-7 or DB25F-7)
Supply: $8.50 ea. (12VDC @ 200/300 mA wall power supply)

*RSCOM2A with all options (DB9F Cable/Enclosure/PS): RSCOM2A-B9FSPS @ $115.00 ea. (Qty. 1-9)

Need a different configuration or more information? Give Ron a Call at 513-874-4796 or 513-638-0228(Cell)

Webstore: RSCOM2A

Popular Products: