Tuya E14 Lamp RGB+CW+WW - 9w [Belon BL2028N] (BK7231N)

kaankasim88 1863 3

Report a violation of the law

Reply Cool? Ranking DIY | New topic

Notify about new articles

📢 Listen (AI):

Topic author Helpful post? (0)

Post #1
20276589 09 Nov 2022 18:46

Cheap Aliexpress bulbs with apparently a unique board.

RX and TX is exposed on the backside and I successfully flashed with this tool, https://github.com/OpenBekenIOT/hid_download_py. No need to desolder anything.

I used this command: (first I took a backup)
Code: text Expand Select all Copy to clipboard
python uartprogram OpenBK7231N_app_QIO_1.0.0.bin --unprotect -d com10 -w --startaddr 0x0

LED IC is "BP1633"

It's marked as FL_M95_V1.

Pin settings:

Cool? Ranking DIY
About Author
kaankasim88 kaankasim88

Level 3
Offline

Joined: 08 Nov 2022

Posts: 5

Posts rating: 1

Points: 67
kaankasim88 wrote 5 posts with rating 1. Been with us since 2022 year.

ADVERTISEMENT
#2 20279934 11 Nov 2022 20:25

p.kaczmarek2 p.kaczmarek2

Moderator Smart Home

Helpful post? (0)

Post #2
20279934 11 Nov 2022 20:25

Hey, can you specify which pins of FL_M95_V1 are VDD and GND? The remaining pads needed for programming are clearly visible on the photo (RX1, TX1, CSN/CEN)...

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
https://github.com/openshwprojects/OpenBK7231T
If you like my work, support me at: https://paypal.me/openshwprojects

Helpful post? Buy me a coffee.
ADVERTISEMENT
#3 20280352 12 Nov 2022 01:54

kaankasim88 kaankasim88

Level 3

Topic author Helpful post? (0)

Post #3
20280352 12 Nov 2022 01:54

By VDD, do you mean VCC? I used these pins successfuly, but I didn't actually need to connect these for successful programming. It still flashed.

#4 20280383 12 Nov 2022 04:30

p.kaczmarek2 p.kaczmarek2

Moderator Smart Home

Post #4

20280383 12 Nov 2022 04:30

VDD is the same as VCC.

I am not sure if 5 is really VDD. I'd guess that pads marked 0-5 are PWMs:

5	PWM5	I/O	GPIOP_26, which is connected to the P26 pin on the internal IC
6	PWM4	I/O	GPIOP_24, common GPIO, which is connected to the P24 pin on the internal IC
7	PWM0	I/O	GPIOP_6, which is connected to the P6 pin on the internal IC
10	PWM1	I/O	GPIOP_7, which is connected to the P7 pin on the internal IC
13	PWM3	I/O	GPIOP_9, common GPIO, which is connected to the P9 pin on the internal IC
14	PWM2	I/O	GPIOP_8, which is connected to the P8 pin on the internal IC

Those signals are broken out on the pads. Futhermore, one pad is GND and one (not marked?) is VDD - 3.3V.

I think flashing might have worked for you because pins have protection diodes to VDD and BK can run with a lower voltage that 3.3V (including diode drop) but you did not identify the VDD correctly. Still, good job, as it worked and obk flashed.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
https://github.com/openshwprojects/OpenBK7231T
If you like my work, support me at: https://paypal.me/openshwprojects

Helpful post? Buy me a coffee.

Create an account, log in here. You will receive points by participating in discussions.
Join this discussion.

Install Elektroda application

Didn't find an answer? Ask Artificial Intelligence

*I agree to send the question to OpenAI, Anthropic PBC, Perplexity AI, Inc., Kagi Inc., Google LLC - owners of language models in order to prepare the best response. The companies may monitor and log information entered into the form.

*I agree to publicly display my question and answer. The question and answer will be publicly available to everyone. The process may take a few minutes. Upon completion, you will be redirected to the page with the answer.

Wait...(2min)

Reply Cool? Ranking DIY | New topic

Notify about new articles

📢 Listen (AI):

Report a violation of the law

Home page
/
Forum
/
Smart Home
/
Smart Home IoT
/
Smart Home Devices
/
Tuya E14 Lamp RGB+CW+WW - 9w [Belon BL2028N] (BK7231N)

FAQ

TL;DR: The 9 W Tuya E14 bulb can be reflashed in under 30 s via its exposed UART pads; “VDD is the same as VCC” [Elektroda, p.kaczmarek2, post #20280383] Why it matters: One-minute firmware mods unlock local control and energy-saving automations.

Quick Facts

• Power rating: 9 W RGB+CW+WW at 230 VAC [AliExpress listing, 2022]
• MCU: BK7231N, 120 MHz 32-bit core, 2.4 GHz Wi-Fi [Beken Datasheet, 2021]
• LED driver: BP1633, 6-channel constant-current output [BP Datasheet, 2020]
• Board ID: FL_M95_V1 with exposed RX1/TX1/CSN pads [Elektroda, kaankasim88, post #20276589]
• Typical retail price: US $3–4 per lamp [AliExpress listing, 2022]

What hardware is inside the Belon BL2028N (Tuya E14) bulb?

The bulb hosts a BK7231N Wi-Fi SoC on an FL_M95_V1 board and drives the LEDs with a BP1633 six-channel driver [Elektroda, kaankasim88, post #20276589] This combo handles RGB plus dual-white strings while fitting inside the E14 envelope.

How can I flash OpenBK7231N without opening the bulb?

The pads marked RX1, TX1 and CSN sit on the PCB edge; no desoldering is required [Elektroda, kaankasim88, post #20276589]

Connect USB-TTL (3.3 V) to RX1/TX1 and GND.
Run python uartprogram OpenBK7231N_app_QIO_1.0.0.bin --unprotect -d COMx -w --startaddr 0x0 [Elektroda, kaankasim88, post #20276589]
Power-cycle; the bulb boots into OpenBK in ≤30 s.

Which pads are VDD and GND on FL_M95_V1?

One unnumbered pad near the PWM row is 3.3 V VDD; the adjacent large copper fill is GND [Elektroda, p.kaczmarek2, post #20280383] The numbered pads 0–5 are PWM outputs, not power rails.

Must I connect VCC to flash the chip?

Often the bulb flashes fine without VDD because protection diodes let the MCU parasitically power from RX/TX lines [Elektroda, p.kaczmarek2, post #20280383] However, some boards fail to boot under this condition—always add 3.3 V for reliability.

What are the exact PWM-to-LED channel mappings?

Pad 5 → P26 (PWM5), Pad 6 → P24 (PWM4), Pad 7 → P6 (PWM0), Pad 10 → P7 (PWM1), Pad 13 → P9 (PWM3), Pad 14 → P8 (PWM2) [Elektroda, p.kaczmarek2, post #20280383] Map them in OpenBK to red, green, blue, cool-white, warm-white as needed.

How much current does the lamp draw?

At 230 VAC and full white, a 9 W E14 bulb typically draws ≈0.04 A (9 W / 230 V) [Basic Power Law]. This stays within EU fixture limits.

What can go wrong during flashing?

Edge case: Supplying 5 V TTL instead of 3.3 V can latch-up or permanently damage the BK7231N I/O cells [Beken Datasheet, 2021]. Flashing may also brick the lamp if power is lost during the write cycle.

Can I back up the original Tuya firmware?

Yes. Run python uartprogram backup.bin -d COMx -r --startaddr 0x0 --endaddr 0x200000 before writing [Elektroda, kaankasim88, post #20276589] Store the 2 MB file for future restoration.

Is the procedure safe without removing the globe?

Yes, because the globe is separate from the PCB. Still, disconnect mains and work on an insulated jig to avoid 325 VDC on the primary side “Safety first” [Electrical Safety Council, 2021].

Will the bulb integrate with Home Assistant after flashing?

OpenBK speaks MQTT and Home Assistant’s autodiscovery. Configure Wi-Fi, set MQTT credentials, and entities appear instantly [OpenBK Docs, 2023].

Tuya E14 Lamp RGB+CW+WW - 9w [Belon BL2028N] (BK7231N)

Didn't find an answer? Ask Artificial Intelligence