SurrealBoot — Standalone RP2350 Tether Booter

Target Board & Base Firmware

Pick your board model. If you haven't flashed the base firmware yet, hold BOOTSEL on your board, plug it in, and copy the .uf2 file to the RPI-RP2 drive.

Waveshare RP2350 USB-A Recommended

Built-in USB-A host port · GP12 (DP) / GP13 (DM)

Waveshare RP2350-Zero

Compact board · GP12 (DP) / GP13 (DM)

Pimoroni Tiny 2350

Castellated module · GP16 (DP) / GP17 (DM)

Raspberry Pi Pico 2

Standard Pico 2 form factor · GP16 (DP) / GP17 (DM)

123 KB UF2

Flash Boot Payload (iBSS.boot)

Provide the iBSS.boot stitched payload generated for your device (e.g. from surrealra1n). The tool compresses it in-browser with LZ4 and writes it to flash offset 0x10020000 over USB Serial.

Select or drag & drop iBSS.boot Typically 2.0 – 2.8 MB raw payload

LED Operating Guide

Once flashed, SurrealBoot runs standalone without a computer. Connect the RP2350 to power, plug in the iPhone, and follow the RGB LED states:

Solid Orange

Idle / Listening for USB host connection.
Solid Magenta (Countdown)

Recovery detected. Hold Volume Down + Power. Board injects reboot packet at tick 2.
Solid Cyan

Release Power, keep holding Volume Down for 8s.
Blinking White

Release all buttons. Waiting for DFU enumeration.
Solid Blue

Running USBLiter8 exploit.
Solid Green

Boot payload streamed to memory. iPhone boots!

Hardware Notes

Waveshare RP2350 USB-A

The USB-A female port is wired directly to VSYS for 5V power and GP12/13 for data. Our firmware automatically handles the board's onboard R13 resistor with active USB bus resets.

Cables & Connection

Use a standard USB-A to Lightning cable connected between the board's USB-A host port and the iPhone. Keep the board powered via USB-C or 5V pin.

Supported Hardware

View the supported devices wiki →