# FlopperZiro: a DIY Flipper Zero clone on STM32 and Arduino > FlopperZiro is a GPL-3.0 hardware project that recreates the Flipper Zero's core capabilities using an STM32-L432KC, off-the-shelf 433 MHz modules, and the Arduino IDE. The firmware reached v1.0.0 in June 2026 with RF, IR, and partial RFID support, though ISO14443-B emulation and comprehensive documentation are both listed as not yet done. **lraton/FlopperZiro** — A Flipper Zero clone, but cheapest, DIY and simply Open Source, made with Arduino IDE - Repository: https://github.com/lraton/FlopperZiro - Website: http://flopperziro.iraton.it/ - Stars: 2,090 · Forks: 108 - Language: C++ - License: GPL-3.0 - Published: 2026-10-11 · Updated: 2026-10-11 · Language: en - Canonical page: https://hysenlabs.com/projects/lraton-flopperziro ## The STM32-L432KC microcontroller and what drives the component choices FlopperZiro centers on the STM32-L432KC microcontroller, flanked by an FS1000A module for 433 MHz transmission and an RXB12 for 433 MHz reception as two separate chips that handle transmit and receive independently. NFC and RFID work goes to a PN532 controller, with a note in the hardware list that a PN7150 is "under evaluation" as a potential alternative or addition. The display is an SSD1306 OLED panel at 128x64 pixels connected over I2C. Storage is a TF MicroSD card shield. Power management combines a TP4056 battery charger with a DC-DC 5V boost converter drawing from a 3.7V LiPo cell, and an infrared LED and receiver pair handle the IR side. The rest of the board consists of a 2N2222A transistor, six tactile push buttons sized 6x6x8mm, and a SMD Micro USB port. The PCB and Schematic/ folder at the repository root holds the design files, so building a unit from scratch means starting there rather than trying to reconstruct the circuit from the feature list alone. A 3D-printed housing is available on Printables as model 1142768-flopper-ziro-shell for anyone who wants a finished enclosure. ## Flashing from the Arduino IDE, with no prebuilt binary and no build documentation The firmware lives under main/ in the repository and is uploaded through the Arduino IDE, which is the full installation path the project provides. No prebuilt binary is offered, no package manager entry exists, and no flash script appears in the repository listing. Anyone building a unit must have the Arduino IDE configured for the STM32-L432KC and load the sketch manually over the SMD Micro USB port. At the repository root there is an SD Root Folder/ directory whose contents point to the directory layout the firmware expects to find on the MicroSD card. Several features save and load data from that card: IR signal recordings, captured RF data, and RFID tag states all go through the same MicroSD storage layer. Copying those SD Root Folder/ contents before first boot is the implied setup step that makes those persistence features work as described. Comprehensive code and hardware documentation is marked as not yet done on the roadmap, which means the schematic in PCB and Schematic/ and the source code under main/ are currently the only references available. Anyone who needs to modify or extend the firmware starts from reading the source without any written explanation of how the modules connect. ## 433 MHz capture and IR replay both write to MicroSD for later playback The FS1000A and RXB12 modules handle 433 MHz transmission and reception as separate chips, and the roadmap confirms that the RF scanner and transmitter logic, along with SD save and load states, are all finished. Captured RF data is written to the MicroSD card and can be replayed from the menu on demand without restarting or reconfiguring the device. Infrared operates the same way. The IR LED and receiver capture incoming signals, the firmware stores them to the MicroSD card, and the menu offers replay from any saved file. Both the RF and IR persistence features are marked complete in the roadmap. What neither the RF nor the IR documentation covers is the range of protocols or signal types the firmware can decode within those bands. The feature list confirms each capability exists and the roadmap confirms each is done, but the specifics of what the firmware handles sit in the source under main/ rather than in any written document. ## RFID emulation stops before ISO14443-B, while the PN7150 integration remains untested The RFID and NFC subsystem uses a PN532. Three sub-tasks are marked complete in the roadmap: reading standard UIDs, emulation and APDU handling, and SD save states for RFID tags. One sub-task is explicitly not complete: "Implement ISO14443-B support." That gap is specific and practical. The firmware can read standard UIDs and emulate cards, but it cannot yet handle the ISO14443-B variant of the proximity card standard, so anyone whose use case includes cards or documents that require ISO14443-B will find FlopperZiro incomplete for that purpose in v1.0.0. Reading the hardware list and the roadmap together reveals a connection the README does not state explicitly. The hardware component table lists the current NFC controller as "PN532 (PN7150 under evaluation)," and the hardware roadmap has "PN7150 module integration testing" as an open item that sits directly alongside the ISO14443-B software item. Both remain unfinished, and the README offers no explanation of what role the PN7150 is expected to play or what is blocking its integration. ## BadUSB runs Rubber Ducky scripts with no example file and no documented storage path BadUSB integration is marked complete in the roadmap, allowing FlopperZiro to act as a USB keyboard and run Rubber Ducky scripts when connected to a computer. Rubber Ducky is a line-based scripting format originally developed for USB keyboard injection devices, and the scripts send keystrokes to the host at speed once the connection is established. What the README does not cover is where scripts are stored, how the device selects one from the menu, or what file path the firmware reads from the MicroSD card. There is no example script file named, no file extension given, and no directory path documented anywhere in the README. The SD Root Folder/ directory in the repository is the natural place to look for that layout, but the README itself provides no file name and no structural description for the BadUSB payload path. Working out how the feature loads scripts requires reading the source under main/ or experimenting with the card layout directly. ## A display timing bug after each Arduino IDE upload requires a Serial Monitor reset to clear After uploading new firmware through the Arduino IDE, the SSD1306 display can remain completely black. The README identifies this as "a known hardware timing quirk where the IDE's automatic reset doesn't properly reboot the display," and the documented fix is to open the Serial Monitor or Debugger panel in the Arduino IDE, which triggers a software reset over USB and brings the display up normally. The README says this happens occasionally rather than on every upload, but it affects every build session that ends with a quick functionality check. Because the natural response to a blank display after flashing is to assume the upload failed, knowing about this quirk before the first build session saves time. The fix requires the IDE to remain connected when testing, so a post-flash check cannot be done on a standalone powered board without the USB cable and the IDE still open. ## The roadmap shows most features done, but NFC and documentation items remain open FlopperZiro tagged v1.0.0 on 2026-06-01, with the last push to main on 2026-06-24, and the repository is not archived. The software roadmap shows most planned work complete: SD browser, save/load states, RF scanner, menu navigation, BadUSB, and IR processing are all marked done. Both PCB design iterations on the hardware side are also ticked off. Two items remain open across the roadmap sections. ISO14443-B support is the pending software item inside the RFID subsystem. PN7150 module integration testing is the pending hardware item. Both affect the same part of the device, as noted in the section on RFID above. The documentation gap runs wider than either of those. "Comprehensive code and hardware documentation" is listed as not yet done in the Documentation section of the roadmap, meaning the schematic files in PCB and Schematic/ and the source code under main/ are available but no written guide accompanies them. That is the practical cost for anyone who wants to go beyond what v1.0.0 already does without spending time reverse-engineering the firmware from source. ## Conclusion FlopperZiro suits a maker who wants to learn how 433 MHz radio capture, IR replay, NFC emulation, and BadUSB work by building and programming the hardware, and who is comfortable working from source code and schematics without a written guide. The device does not yet read or emulate ISO14443-B cards, and the documentation item on the roadmap remains open. Before ordering components, read the PCB and Schematic/ folder against the hardware component list to confirm PN532 or PN7150 availability, and check the SD Root Folder/ to understand the card layout the firmware needs. ## FAQ ### What is FlopperZiro? FlopperZiro is an open-source DIY multi-tool inspired by the Flipper Zero, built around an STM32-L432KC microcontroller and programmed through the Arduino IDE. It handles 433 MHz RF capture and replay, infrared signal capture and replay, partial RFID and NFC support, and BadUSB script execution. ### What components are needed to build FlopperZiro? The hardware list includes the STM32-L432KC microcontroller, an FS1000A transmitter and RXB12 receiver for 433 MHz RF, a PN532 for RFID and NFC, an SSD1306 OLED display, a TF MicroSD card shield, and a 3.7V LiPo battery with a TP4056 charger and a DC-DC 5V boost converter. PCB design files are in the PCB and Schematic/ folder of the repository. ### Does FlopperZiro support NFC card emulation? The roadmap marks RFID emulation and APDU handling as complete, but ISO14443-B support is not yet implemented. A PN7150 module is listed as under evaluation for hardware integration, and that work is also incomplete in v1.0.0. ### How do I program FlopperZiro? The README states the device is fully programmable via the Arduino IDE. There is no prebuilt binary; the firmware is under main/ in the repository and is uploaded over the device's SMD Micro USB port. ### Why does the FlopperZiro display stay black after uploading? The README identifies this as a known hardware timing quirk where the Arduino IDE's automatic reset does not properly reboot the display. Opening the Serial Monitor or Debugger in the IDE sends a software reset over USB, and the display starts up normally. ## Sources - [License: GPL-3.0](https://github.com/lraton/FlopperZiro/blob/main/LICENSE) - [lraton/FlopperZiro on GitHub](https://github.com/lraton/FlopperZiro) - [Project website](http://flopperziro.iraton.it/) - [README](https://github.com/lraton/FlopperZiro/blob/main/README.md) - [Releases](https://github.com/lraton/FlopperZiro/releases) --- Hysen Labs editorial analysis, written from the project's own repository and release notes. Cite the canonical page: https://hysenlabs.com/projects/lraton-flopperziro