Mayhem-Firmware is a custom firmware for the PortaPack add-on that transforms a HackRF software-defined radio into a standalone handheld device capable of receiving, transmitting, and analyzing radio signals across a wide frequency range. The firmware provides a complete operational environment with an event-driven touchscreen interface, a menu-driven application launcher, and a real-time sample streaming pipeline that connects the hardware abstraction layer to a suite of modular applications. All user data, including frequency presets, captures, and configuration files, are stored on a removable SD card, and a USB serial command interface enables remote control, debugging, and scripting without the graphical interface.
The firmware distinguishes itself through its extensible, application-based architecture. It includes a module-based protocol decoder that supports dozens of analog and digital radio standards—such as ADS‑B, AIS, APRS, POCSAG, and weather satellite signals—both for reception and transmission. Signal capture and replay let users record raw IQ samples to storage and reproduce them later for analysis or retransmission. Two‑way voice and packet radio communication is supported via a microphone and a KISS TNC, while spectrum analysis tools provide real‑time waterfall displays, frequency scanning, and signal reconnaissance. The platform also offers a range of built‑in utilities, including file management, device diagnostics, and entertainment applications such as classic arcade games.
Beyond radio‑specific capabilities, the firmware provides full device management through on‑screen menus and a serial console, allowing users to calibrate hardware, customize display themes and waterfall color palettes, and manage files and frequency lists. It can also be switched into standard HackRF mode for use with host‑based SDR software. The firmware is open‑source and intended for installation on the PortaPack Mayhem hardware, turning it into a versatile SDR utility and entertainment platform.