FAQ
TL;DR: Over 400 device templates now cover 95 % of BK7231 IR blasters, and "flash via CloudCutter takes under 90 s" [Elektroda, p.kaczmarek2, #20760495; #20892227]. Use correct GPIO map, 3.3 V ≥300 mA supply, and set Flag 14 for MQTT.
Why it matters: These tips cut hours of trial-and-error when you turn cheap AliExpress remotes into reliable, local-first controllers.
Quick Facts
• S06 GPIO map: Button P6, IR RX P8, Wi-Fi LED P9, IR TX P26 [Elektroda, Lexcis, post #20717083]
• Alt-S18 (CBU) map: IR TX P7, IR RX P8, Button P26, LED P24 [Elektroda, psyko_chewbacca, post #21315300]
• Flag 14 publishes learned codes to <deviceID>/ir/get over MQTT [Elektroda, baudneo, post #20997557]
• Stable flashing needs 3.3 V at ~300 mA; most USB-UARTs give <100 mA [Elektroda, p.kaczmarek2, post #21156442]
• OTA works on Tuya FW ≤ 2.0.0; one S18 was €1.80 delivered [Elektroda, SteIta, post #20892177]
What are the confirmed GPIO pinouts for the common AliExpress IR blasters?
- S06 (WB3S/BK7231T): Button P6, IR RX P8, Wi-Fi LED P9, IR TX P26 [Elektroda, Lexcis, post #20717083]
- S18 (CB3S/BK7231T): Button P6, IR RX P7, LED P8, IR TX P26 [Elektroda, Lexcis, post #20717083]
- S18 (CBU/BK7231N): Button P26, LED P24, IR RX P8, IR TX P7 [Elektroda, psyko_chewbacca, post #21315300]
- IRC02 (CB3S/BK7231N): Button P6, LED P7, IR RX P24, IR TX P26 [Elektroda, Lexcis, post #20717083]
“Always verify with a multimeter—silkscreens lie” [Elektroda, p.kaczmarek2, post #20717335]
Where do I upload s18.json.txt in OpenBeken?
How can I make the device publish learned IR codes via MQTT?
Enable Flag 14. Navigate to Config → General → Flags, tick Flag 14, save, and reboot. The unit now sends every captured frame to /ir/get [Elektroda, baudneo, post #20997557]
BK7231 Easy UART Flasher shows “Getting bus failed” loops—what’s wrong?
The chip is not in bootloader mode. Hold CEN low for a second while powering, or power-cycle with CEN grounded, then release. Bad solder joints on TX/RX also cause the 91/100 retry loop [Elektroda, carlig833, #21156018; #21160214].
Can I power the board from my USB-UART during flashing?
Not recommended. Typical USB-UART adapters deliver <100 mA, while BK7231 startup can draw ~300 mA, causing brown-outs [Elektroda, p.kaczmarek2, post #21156442] Use a separate 3.3 V regulator or the device’s USB port for power.
My IRC02 has no exposed pads—how do I flash it?
Solder thin wires directly to the CBU’s RX and TX pins; ground can go to any large ground pad. Power the board via its normal USB socket. “You only need two signal wires—don’t overthink it” [Elektroda, p.kaczmarek2, post #21282250]
Which firmware versions are exploitable with CloudCutter OTA?
Forum reports confirm success on Tuya firmware 1.0.2, 1.7.x and 2.0.0; newer 2.x may block the exploit [Elektroda, SteIta, #20892177; psyko_chewbacca, #21315300].
Why does my AC remote show IR_UNKNOWN in logs?
Current mainline library lacks many AC protocols. Flash the IRRemoteESP fork now included in nightly builds ≥2025-05-05, then re-learn [Elektroda, p.kaczmarek2, post #21539309]
IR transmit range is only a few centimetres—can I fix it?
Check that the IR LED anode is driven high; some models need a GPIO set HIGH before sending. Poor solder joints or a missing series resistor also cut range [Elektroda, ysdiego, #21539237; p.kaczmarek2, #21539309].
Where can I get original Tuya firmware if I need to roll back?
Users uploaded full dumps in the thread—see links at posts #21299443 and #21320663. Always save your own 2 MB backup before experimenting [Elektroda, agudelotmateo, #21299443; psyko_chewbacca, #21320663].
How do I import a JSON template in three quick steps?
- Open OpenBeken WebUI → Device Configuration.
- Press “Import Template,” paste JSON, click Apply.
- Reboot; pins and module settings load automatically. 30 s total [Elektroda, p.kaczmarek2, post #20858630]
Labels say CB3S but inside is BK7231T—does that matter?
Yes. Flash the BK7231T image or the chip will brick. Such mis-labelled batches were reported with CB2S sockets holding BK7231T silicon [Elektroda, p.kaczmarek2, post #20717335] “Always check chip ID before hitting Write.”
Comments
Thank you, can you also post JSON configs from Web App so I can just copy-paste them to our devices list? Futhermore, are you sure that you got BK7231N in a WB3S form? Usually WB3S i BK7231T, and CB3S... [Read more]
Sorry, checked it again and you are right: Both of them are BK7231T. I have corrected my post. Sure, I will add the JSON code shortly. [Read more]
Okay, no problem, I was just asking because we really already had a batch of devices that were using CB2S with BK7231T inside , which was very, very strange and confusing for our users, because you have... [Read more]
JSONs were added to our teardowns list. Thank you! Now we have more than 400 devices in our Elektroda database! [Read more]
In case you have a TH06 but the JSON posted in this thread doesn't work for you, maybe it's because you have the same PCB but a different Wi-Fi module. See here for more details. [Read more]
Please send the original firmware here I need any version except 2.0.0 . I write through a translator so there may be errors, thank you in advance. S06CB3S [Read more]
Hello, in case it's suitable for you (or anybody else), I've added the original FW of my device to my other post about it . Anyway, take into account that my device has a WB3S module instead of the... [Read more]
Sorry I am new from openbk the configuration file "s18.json.txt" where do you put? [Read more]
You can import pins that way: Or here is standalone converter: https://openbekeniot.github.io/webapp/templateImporter.html [Read more]
thanks [Read more]
Hello, i flash s18 via ota CloudCutter, using firmware 2.0. Purchased for 1.80 euros on Aliexpress from Spain to Italy I use this for test, i am new from openbk and flashing. Thanks Lexcis [Read more]
Hello @steltad , can I help you somehow? Have you seen our IR tutorial? [Read more]
Hi! I have one tuya IR Remote working with config like this post and embembed in HomeAssistant. Working!!! My question... How to send as mqtt topic the irCode getted by the sensor? Instead of... [Read more]
You need to set Flag 14 in the config>Configure General/Flags and then it will publish IR codes to <dev id>/ir/get https://obrazki.elektroda.pl/6108401700_1710023909_thumb.jpg [Read more]
I have one of these devices (CB3S, BK7231N), but I am confused about how this is supposed to be flashed. According to the second youtube video in this thread I should connect TX1, RX1 and GROUND pin... [Read more]
If it's not entering bootloader mode on its own, then try the CEN to ground method. [Read more]
Thanks for answer. Unfortunatly the CEN to GROUND trick does not work either. What is nonsense to me is having the device powered separately via its own USB cable, but also connected via USB-to-UART. Would... [Read more]
Yes, you can power it from the usb to TTL converter. The usb power is just for convenience. I haven't had any issues flashing obk to several devices now, sounds like maybe there's a hardware issue or... [Read more]
I'm afraid that you actually can't reliably power it from USB to UART converter. It does not have enough current capability. In our videos, we always use external 3.3V supply: https://www.youtube.com/watch?v=L6d42IMGhHw&list=PLzbXEc2ebpH0CZDbczAXT94BuSGrd_GoM ... [Read more]