
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.

USB-derived 5 V supply exposed on the TTL side; product page states the adapter provides 5V power for small projects.
3.3 V supply exposed on the TTL side; product page states the adapter provides 3V power with matching ground.
Ground reference, exposed with the TTL/RS232 terminal groups in the product diagram.
5 V logic-level UART transmit from the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND.
5 V logic-level UART receive into the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND.
RS-232 transmit terminal shown in the manufacturer diagram.
RS-232 receive terminal shown in the manufacturer diagram.
RS-232 request-to-send terminal shown in the manufacturer diagram.
RS-232 clear-to-send terminal shown in the manufacturer diagram.
RS-232 data-carrier-detect terminal shown in the manufacturer diagram.
RS-232 data-set-ready terminal shown in the manufacturer diagram.
RS-232 data-terminal-ready terminal shown in the manufacturer diagram.
RS-232 ring-indicator terminal shown in the manufacturer diagram.
RS-485/RS-422 transmit positive/A terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
RS-485/RS-422 transmit negative/B terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
RS-485/RS-422 receive positive terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
RS-485/RS-422 receive negative terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
| Pin | Type | Function | Voltage |
|---|---|---|---|
| 5V | Power | USB-derived 5 V supply exposed on the TTL side; product page states the adapter provides 5V power for small projects. | 5V from USB, limited current for small projects |
| 3.3V | Power | 3.3 V supply exposed on the TTL side; product page states the adapter provides 3V power with matching ground. | 3.3V supply output |
| GND | Ground | Ground reference, exposed with the TTL/RS232 terminal groups in the product diagram. | 0V reference |
| TTL TXD | Signal | 5 V logic-level UART transmit from the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND. | 5V logic level |
| TTL RXD | Signal | 5 V logic-level UART receive into the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND. | 5V logic level |
| RS232 TXD | Signal | RS-232 transmit terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 RXD | Signal | RS-232 receive terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 RTS | Signal | RS-232 request-to-send terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 CTS | Signal | RS-232 clear-to-send terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 DCD | Signal | RS-232 data-carrier-detect terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 DSR | Signal | RS-232 data-set-ready terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 DTR | Signal | RS-232 data-terminal-ready terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS232 RI | Signal | RS-232 ring-indicator terminal shown in the manufacturer diagram. | RS-232 signalling |
| RS485422 TX+A | Unknown | RS-485/RS-422 transmit positive/A terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips. | RS-485/RS-422 differential signalling |
| RS485422 TX-B | Unknown | RS-485/RS-422 transmit negative/B terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips. | RS-485/RS-422 differential signalling |
| RS485422 RX+ | Unknown | RS-485/RS-422 receive positive terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips. | RS-485/RS-422 differential signalling |
| RS485422 RX- | Unknown | RS-485/RS-422 receive negative terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips. | RS-485/RS-422 differential signalling |
USB-derived 5 V supply exposed on the TTL side; product page states the adapter provides 5V power for small projects.
3.3 V supply exposed on the TTL side; product page states the adapter provides 3V power with matching ground.
Ground reference, exposed with the TTL/RS232 terminal groups in the product diagram.
5 V logic-level UART transmit from the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND.
5 V logic-level UART receive into the USB serial adapter; product page states the UART side exposes RX/TX and 5V/3V/GND.
RS-232 transmit terminal shown in the manufacturer diagram.
RS-232 receive terminal shown in the manufacturer diagram.
RS-232 request-to-send terminal shown in the manufacturer diagram.
RS-232 clear-to-send terminal shown in the manufacturer diagram.
RS-232 data-carrier-detect terminal shown in the manufacturer diagram.
RS-232 data-set-ready terminal shown in the manufacturer diagram.
RS-232 data-terminal-ready terminal shown in the manufacturer diagram.
RS-232 ring-indicator terminal shown in the manufacturer diagram.
RS-485/RS-422 transmit positive/A terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
RS-485/RS-422 transmit negative/B terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
RS-485/RS-422 receive positive terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
RS-485/RS-422 receive negative terminal shown in the manufacturer diagram; product page states RX/TX lines connect to MAX485 chips.
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.
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