Flash the Cheap Yellow Display (CYD)
Install Bruce or ESP32 Marauder on your Cheap Yellow Display (the ESP32-2432S028) directly from this page — nothing to download or install. You need Chrome, Edge or Firefox 151+ on a desktop computer and a USB data cable.
Bruce or Marauder — which one?
Pick the firmware in the Firmware type selector, then choose your board's USB variant in the Version list.
| Firmware | Best for | Radios |
|---|---|---|
| Marauder | Wi-Fi / Bluetooth recon, deauth, probe & beacon work | Uses the CYD's built-in ESP32 radio |
| Bruce | All-round multitool: Sub-GHz, RF, IR, RFID, BadUSB | Most RF features need add-on modules |
Longer answer, including licences and how both compare to GhostESP and 5Ghost: which firmware should I flash?
Which CYD variant do I have?
Check the USB ports on the bottom edge of the board:
- One micro-USB port → the classic 2432S028.
- A micro-USB plus a USB-C port → the 2USB variant.
They use different firmware images. Select the matching variant in the Version list before flashing.
Which browsers can flash the CYD?
| Browser | Supported |
|---|---|
| Chrome / Edge (desktop) | ✅ Yes |
| Chrome (Android) | ✅ Yes |
| Firefox 151+ (desktop) | ✅ Yes — first use adds a permission add-on |
| Safari (macOS / iOS) | ❌ No |
| Firefox (Android) | ❌ No |
Browser flashing relies on the Web Serial API: Chrome and Edge on desktop, Chrome on Android, and — since Firefox 151 for desktop (May 2026) — Firefox. Safari and every browser on iOS are out; see Web Serial is not supported.
Troubleshooting
| Symptom | Fix |
|---|---|
| No port shows in the picker | Follow No serial port detected; identify CH340 vs CP2102 before using the driver guide. |
| "Failed to connect" / sync error | Use the CYD download-mode sequence, then follow Timed out waiting for packet header. |
| Screen blank after flashing | You likely flashed the wrong USB variant. Reconnect and flash the matching variant — it recovers, it is not bricked. |
| Wrong chip detected | Close any app holding the port; see Failed to open serial port. |
| CYD reboots unexpectedly on Bruce (e.g. on RF Scan) | Re-flash the default version — it is always the current upstream release, and Bruce rewrote its RF stack in 1.16 (2026-07-24) to fix a class of RF reboots. If it still happens on the newest release, report it with your board and the exact menu at the Bruce issue tracker. |
What are Bruce and Marauder?
Bruce is an open-source ESP32 firmware for wireless and hardware research, published at github.com/BruceDevices/firmware under AGPL-3.0. ESP32 Marauder is an open-source Wi-Fi/Bluetooth analysis suite, published at github.com/justcallmekoko/ESP32Marauder under the MIT license.
Frequently asked questions
Which Bruce version should I flash on the CYD?
Flash the default. This page always offers the current upstream stable release — Bruce 1.16.1 today — and it is preselected for you; the list is refreshed from the Bruce project on every build, so you never have to look up a version number. Older releases are published at github.com/BruceDevices/firmware if you specifically need one. Every build we flash is a complete image, so you can move between releases at any time with a single flash.
What is the Cheap Yellow Display (CYD)?
The CYD is the nickname for a family of low-cost ESP32 development boards with a built-in color touchscreen, popularised by the ESP32-2432S028. All variants covered here use a plain ESP32-WROOM chip and are popular for running Bruce and ESP32 Marauder firmware.
Which CYD variant do I have?
Check the USB port(s) on the bottom edge: one micro-USB = 2432S028. Micro-USB + USB-C = 2USB. A 3.5" screen = 3248S035C (capacitive) or 3248S035R (resistive). Look at your board's silkscreen or PCB label for the exact model number. The 2432W328C variants add a CC1101 header; the 2432W328R and S024R share one image.
Should I flash Bruce or Marauder on my CYD?
Marauder focuses on Wi-Fi and Bluetooth reconnaissance and works out of the box with the CYD's built-in radio. Bruce is a broader multitool (Sub-GHz, RF, IR, RFID, BadUSB) but needs add-on radio modules for most RF features. Pick the firmware in the Firmware type selector, then choose your exact board variant.
I flashed the wrong variant and the screen is blank — did I brick it?
No. The wrong variant boots but the display/touch may not work. Reconnect and flash the correct variant (or hold BOOT while plugging in USB to force download mode), and it will recover.
Does the nm-cyd-c5 (ESP32-C5) work with this flasher?
No. The nm-cyd-c5 uses an ESP32-C5 chip (different architecture, dual-band Wi-Fi) and is not a plain ESP32 variant. It requires a separate firmware and flasher page. We're working on it — check back soon.
Which browsers can flash the CYD?
Chrome or Edge on desktop, Chrome on Android, or Firefox 151+ on desktop. Browser flashing uses the Web Serial API; in Firefox the first connection also adds a permission add-on. Safari and every browser on iOS cannot flash.
WARNING
For educational and lawful network-research purposes only. Comply with all applicable laws in your jurisdiction.