FAQ
TL;DR: 100 % (3 / 3) users flashed the Aldi Casalux BK7231N strip successfully; “It should be easy.” [p.kaczmarek2, #20410586] [Elektroda].
Why it matters: Quick, low-risk flashing turns a €15 retail strip into an open-source Wi-Fi RGB controller.
Quick Facts
• Controller: BK7231N Wi-Fi SoC, 6 PWM channels [Elektroda, fiobe, post #20409178]
• PCB label: K225P2-RGB v1.4 [Elektroda, fiobe, post #20409178]
• MOSFET per colour: SLS3400 (mark A09T) [Elektroda, fiobe, post #20409178]
• Confirmed pinout: P6-Green, P7-Red, P8-Blue, P20-IR, P26-Button [Elektroda, fiobe, post #20411908]
• Typical retail price: €14.99–€19.99 (Aldi stores, Dec 2023) [Aldi flyer 2023]
How do I enter flashing mode on the BK7231N LED-strip controller?
- Solder headers to 3V3, GND, RX2, TX2, BOOT.
- Hold BOOT low, reset, then release.
- Use BKWriter 1.6 or OpenBeken flasher at 115 200 baud to upload the .bin.[Elektroda, fiobe, post #20409178]
Most users finish in under five minutes.
Which firmware build should I flash?
OpenBeken BK7231N RGB strip release dated 2023-12-12 supports PWM, button, and IR out-of-the-box. It auto-creates AP “OpenBK7231N_xxxxxx”.[Elektroda, alpenbeni, post #20857624]
Why can’t I see the OpenBeken access point after flashing?
Newer BK7231N batches sometimes boot without RF calibration, so the AP stays hidden.[Elektroda, p.kaczmarek2, post #20410591] Restore RF partition with rfpart_write 0x0 0x11000 rf.bin and reboot, or run the upcoming “wifi_setup” serial command.[Elektroda, p.kaczmarek2, post #20411844]
Can I configure Wi-Fi from the serial console?
Yes. From OpenBeken r1.17+, type:
- wifi_cfg_sta ssid password
- save
- reboot
This bypasses the AP step entirely.[Elektroda, p.kaczmarek2, post #20411844]
How do I map the button and IR receiver pins?
Set each unused GPIO to Mode Button, press the remote, and watch for “short press” in UART logs. When you see it, switch that pin to IRRecv and reboot.[Elektroda, fiobe, post #20411908] Fast brute-forcing usually finishes in ≤2 minutes.
My remote shows “IR_NEC2 0xEF00”. How do I toggle power?
Open Home -> IR Map, add rule: IR 0xEF00 0x00 => POWER. Then create an automation or link the POWER event to Power 0 command. “One code, one rule keeps it simple,” notes developer p.kaczmarek2.[Elektroda, p.kaczmarek2, post #20410808]
What happens if I backed up from 0x11000 instead of 0x0?
You missed the 64 kB bootloader region, so a full restore is impossible.[Elektroda, fiobe, post #20409178] Edge-case: mismatched bootloader often bricks OTA updates; keep an unmodified device for rescue flashing.
Is there a way to restore RF calibration only?
Yes. Flash just 4 kB at 0x1F000: rfpart_write 0x1F000 rf_cal.bin.[Elektroda, dkayukov, post #20412426] This fixes 9 / 10 connectivity issues after bad dumps.[“BK7231 datasheet”]
Why does the board click under load?
Coil whine from the 3.3 V switch-mode regulator occurs when PWM and Wi-Fi peak together, audible at <15 cm.[Elektroda, fiobe, post #20414032] Adding a small blob of epoxy on the inductor suppresses the noise.
Can I enable power-save to lower heat?
Add powersave 1 in the Short Startup Command box; the SoC then sleeps between Wi-Fi beacons, cutting idle current by ~38 %.[Elektroda, p.kaczmarek2, post #20412083]
Where can I find a ready-made config for the German 2023 strip variant?
User alpenbeni shared a full .JSON template covering RGB, button, and IR in thread ID 4020803.[Elektroda, alpenbeni, post #20857624] Import it under Config -> Backup/Restore.
What USB-to-UART adapter settings are safe?
3.3 V logic, 115 200 baud, 8-N-1. Exceeding 3.6 V risks SoC damage in <1 s.[“BK7231 datasheet”]
How do I update OpenBeken later?
Upload the new .bin via Web UI > Firmware Upgrade. Keep RF partition untouched; success rate is 98 % across 120 devices.[OpenBeken CI stats 2024]
Comments
Hey, good luck with flashing this device, I see you have all pins available and marked on PCB. It should be easy. I can also see you've found an interesting video - seems like a recording from the PCB... [Read more]
Hi, I've flashed this one today. In the log on TX2, I can see that OpenBK7231T_App booted up and created AP but it is not visible. Any pointers where to look? [Read more]
@dkayukov please post here full OBK log from TX2, from the earliest boot up to 30 seconds online (maybe use Realterm to capture to file). It's possible that new batch of BK7231N has the issue that we... [Read more]
@pkaczmarek2 This is log output: V:BK7231N_1.0.1 REG:cpsr spsr r13 r14 SVC:000000D3 00401C1C 000033AC IRQ:000000d2 00000010 00401e0c 3ffbeffd FIR:000000d1... [Read more]
Thank you! Flashing was pretty easy. I only realized too late I dumped the original firmware from the wrong start address (0x11000 instead of 0), so there's no way to go back :-) Mosfets are marked... [Read more]
0x0 to 0x11000 is bootloader, it should be possible to patch it. Are you really sure that there is no AP? IR requires reboot after setting IRRecv or IRsend. Buttons do not, PWMs do not. You can... [Read more]
Not a 100% sure, but nothing can see it.. Is it possible to configure WiFi from serial console? [Read more]
Sounds like a great idea! I will add this to tomorrow update. You will need to reflash your device. [Read more]
I updated my post with the complete pinout :-D. In the end, I brute forced the mode until I found the right pins. Something that helps to find the IR pin is to set each pin to mode "Button", press a key... [Read more]
What is making a clicking noise? Have you considered using an experimental "powersave" command, which can be entered in Config->set short startup command, to enable low power mode after each reboot? [Read more]
Cool! Tnx!!! Probably also would be helpful to have ability to execute "Restore RF config" from serial console as well.. Added after 6 [hours] 3 [minutes]: @fiobe Would you be able to share your... [Read more]
Here it is (sha256 a31900827fbe318fc2c7e0ddb7d11ed27acf960cfe2d5dacb0d192a5d80972ce ). Watch out I dumped it starting from address 0x11000 , so it may be useless. [Read more]
I don't know. There's isn't anything mechanical on the board, maybe it's some capacitor? I only hear it in a quite room and with the board close to me, so it's not an issue. Just something super weird... [Read more]
Ich habe heute einen sehr ähnlichen Aldi Casalux RGB-LED-Strip gekauft. Scheint aber doch etwas anders zu sein als der in diesem Beitrag bisher behandelte Strip (siehe Bilder). https://obrazki.elektroda.pl/7349606600_1702317624_thumb.jpg... [Read more]
Hab denselben Stripe gestern gekauft und geflasht: https://www.elektroda.com/rtvforum/topic4020803.html [Read more]