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USB to Multi-Protocol Serial Adapter: RS-232 / TTL UART / RS-485

USB to Multi-Protocol Serial Adapter: RS-232 / TTL UART / RS-485 — Adafruit — 5995

USB adapter supporting RS-232, TTL UART, RS-485, and RS-422 on screw-terminal connectors, requiring no soldering. A single adapter covers the four most common serial protocols. Select the active protocol via onboard configuration; screw terminals accept bare wire ends directly.

Pinout

Logical pinout · physical placement not verified
USB TO MULTI-PROTOCOL 5VRS232 DCD3.3VRS232 DSRGNDRS232 DTRTTL TXDRS232 RITTL RXDRS485422 TX+ARS232 TXDRS485422 TX-BRS232 RXDRS485422 RX+RS232 RTSRS485422 RX-RS232 CTS
  • 5V

    USB-derived 5 V supply exposed on the TTL side; product page states the adapter provides 5V power for small projects.

    Type · PowerVoltage · 5V from USB, limited current for small projects
  • 3.3V

    3.3 V supply exposed on the TTL side; product page states the adapter provides 3V power with matching ground.

    Type · PowerVoltage · 3.3V supply output
  • GND

    Ground reference, exposed with the TTL/RS232 terminal groups in the product diagram.

    Type · GroundVoltage · 0V reference
  • TTL TXD

    5 V logic-level UART transmit from the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND.

    Type · SignalVoltage · 5V logic level
  • TTL RXD

    5 V logic-level UART receive into the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND.

    Type · SignalVoltage · 5V logic level
  • RS232 TXD

    RS-232 transmit terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 RXD

    RS-232 receive terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 RTS

    RS-232 request-to-send terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 CTS

    RS-232 clear-to-send terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 DCD

    RS-232 data-carrier-detect terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 DSR

    RS-232 data-set-ready terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 DTR

    RS-232 data-terminal-ready terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS232 RI

    RS-232 ring-indicator terminal shown in the manufacturer diagram.

    Type · SignalVoltage · RS-232 signalling
  • RS485422 TX+A

    RS-485/RS-422 transmit positive/A terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.

    Type · UnknownVoltage · RS-485/RS-422 differential signalling
  • RS485422 TX-B

    RS-485/RS-422 transmit negative/B terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.

    Type · UnknownVoltage · RS-485/RS-422 differential signalling
  • RS485422 RX+

    RS-485/RS-422 receive positive terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.

    Type · UnknownVoltage · RS-485/RS-422 differential signalling
  • RS485422 RX-

    RS-485/RS-422 receive negative terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.

    Type · UnknownVoltage · RS-485/RS-422 differential signalling

Start wiring

Ethernet · UART · SPI · Shield

Confirm the data interface matches your host board.

Module pins: 5V, 3.3V, GND, TTL TXD, TTL RXD, RS232 TXD, RS232 RXD, RS232 RTS. Schematik maps them to your board in the app.

Wired comms

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