RadioMaster ExpressLRS USB UART Flasher V2 USB-C 3.3V/5V RM-CRSF for ELRS Receiver Firmware Update

Overview

The RadioMaster ExpressLRS USB UART Flasher V2 is a USB UART Flasher for reliable ExpressLRS (ELRS) receiver firmware updates and firmware recovery via a serial (UART) connection. V2 upgrades to a USB-C interface and adds a built-in power button for one-touch power cycling during flashing, helping avoid the instability sometimes encountered with Wi-Fi upgrades.

It supports multiple connection methods, including a standard 2.54mm pin output and an RM-CRSF JST-GH port for plug-n-play connection with RadioMaster ER series receivers. For product selection or setup help, contact support@rcdrone.top or visit https://rcdrone.top/.

Key Features

• Upgraded USB-C interface (USB-C cable not included)
• Power button for easy ON/OFF power cycling
• Equipped with multiple protective circuits
• Overcurrent protection and reverse polarity protection
• Over-voltage protection
• Switchable power supply between 3.3V and 5V
• Standard 2.54mm pins
• RM-CRSF JST-GH port for simple plug-n-play connection with RadioMaster ER series receivers
• Pin sockets included
• Dupont cables for convenient testing

Specifications

Compatible Receivers

Using 2.54mm pin output and spring-loaded pin adapter or Test hook adapters:

• All RP SERIES ELRS RECEIVERS

Using regular 2.54mm pin output (Servo plugs):

• ER3C-i 2.4GHz ELRS PWM Receiver
• ER5C-i 2.4GHz ELRS PWM Receiver
• ER4 2.4GHz ELRS PWM Receiver
• ER5A 2.4GHz PWM Receiver
• ER5A V2 2.4GHz PWM Receiver
• ER5C 2.4GHz PWM Receiver
• ER5C V2 2.4GHz PWM Receiver
• ER6G & ER6GV ELRS PWM Receiver

Please note: The second channel is repurposed as a TX for the serial port tool's RX port, while the third channel is repurposed as an RX connected to the serial port tool's TX port.

Firmware upgraded by RM-CRSF interface output:

• ER6 2.4GHz ELRS PWM Receiver
• ER8 2.4GHz ELRS PWM Receiver
• ER8G & ER8GV ELRS PWM Receiver

Please note: The above receivers can be connected to the receiver's CRSF port using a 4-wire CRSF cable.

Firmware Upgrade Instructions

1. Connect the Serial Port Cable with the receiver.
2. Connect to the computer with a USB extension cable, press the receiver's BOOT button, then press the POWER button on the serial tool.
3. Follow the ELRS upgrade tool's instructions to complete the upgrade.

Downloads

• USB to UART driver
• USB UART Tool Connection Guide

Package Includes

• 1 * RadioMaster ExpressLRS USB UART Flasher V2
• 1 * Pogo Probe
• 1 * CRSF Wire
• 1 * 2.54mm Serial Port Cable - Type B
• 1 * Serial Port Test Hook - White
• 1 * Serial Port Test Hook - Green
• 1 * Serial Port Test Hook - Red
• 1 * Serial Port Test Hook - Black
• 1 * User Card

Details

Update and recover ExpressLRS receiver firmware over a stable UART connection using the USB‑C Flasher V2.

Built-in protection circuits help guard against overcurrent and reverse polarity during bench flashing.

A direct serial connection keeps firmware upgrades reliable when Wi‑Fi flashing is unstable.

USB‑C makes connecting to your computer simple, while the flasher powers the receiver during updates.

One-touch power cycling via the onboard button helps speed up boot/flash steps without replugging cables.

Choose from RM‑CRSF plug‑and‑play or standard pin/wire connections to match different receiver layouts.

Everything needed for common setups is included—flasher, CRSF lead, pogo probe, test hooks, and a 2.54mm UART cable.