WSAL17939 – USB TO TTL/en

Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

The Waveshare module converts USB to TTL UART and supports 5 V or 3.3 V via a jumper. It reaches up to 3 Mbit/s; the interface suits microcontrollers, sensors and industrial control devices.

Related products at JW Tech

WSAL17939 – Industrial USB TO TTL Converter, Original FT232RNL, Multi Protection & Systems Support

Technical overview

Interface: USB Type A on the host side; the other side provides a TTL UART signal set (TXD, RXD, RTS#, CTS#, etc.).
Supply voltage: selectable 5 V or 3.3 V for external devices via a jumper.
Baud rate range: from 300 baud up to 3 Mbit/s (FT232RNL).
Operating temperature per source: -15 °C to +70 °C; humidity 5 % to 95 % RH.
Signal pins: TXD/RXD for data transfer; RTS#/CTS# for flow control; DCD#, RI#, DSR# as status signals; RESET# to reset the FT232; CBUS0–CBUS4 as flexible I/O.
Supported operating systems: Windows 7/8/8.1/10/11, macOS, Linux, Android and WinCE.
Windows driver options: VCP (virtual COM port) or D2XX (USB API); the product ships a VCP example.
Linux usage: default drivers available; query device name with “lsusb” or “ls /dev/ttyUSB*”; e.g. “sudo minicom -D /dev/ttyUSB0”.
Android connection: OTG adapter required; the SerialTool app has drivers integrated.
Function check: short-circuit TXD and RXD and send data via a serial debugging tool; a response indicates normal operation.
Pinout with label facing up: top row VCC GND TXD RXD; bottom row 5V GND CTS RTS.

Commands and examples – verify before use:

lsusb
ls /dev/ttyUSB*
sudo minicom -D /dev/ttyUSB0

Notes and version constraints

Exact driver files and download links are not fully reproduced in the source; use the official FTDI driver before installation.
If the COM port is missing after driver install, deleting the COM Name Arbiter registry entry may be needed – only by experienced users.
Knock-offs of this module circulate; verify originality before purchase.
Operation outside the stated temperature and humidity ranges can cause malfunction or damage.
Overvoltage, overcurrent, electrostatic discharge or strong electromagnetic interference can damage the FT232 chip; appropriate protection measures are required.

Source and revision record

USB TO TTL - Waveshare Wiki
Source revision: 67698
Captured: 2026-09-01T02:48:06+00:00
SHA-256: d4775fb934be13f6fd34f74a80cf121175d2d2b90c5c1c6a190de3905e72a484