logo elektroda
logo elektroda
X
logo elektroda
Advanced Search
logo elektroda

New entry for IoT device teardowns list: 16A WIFI Mini Smart Switch

OBeker 2052 1

TL;DR

  • A 16A WIFI Mini Smart Switch from SHUNSHUN in Germany joins the IoT teardown list, and its internal layout differs from similar low-cost smart switches.
  • The layout makes OpenBeken flashing easy through a 4-wire UART hookup: TX1 to RX, RX1 to TX, GND to GND, and 3v3 to UART 3V.
  • The device uses a BK7231N chip in a CB2S module, runs at 115200 baud, and its Tuya section starts at 2023424.
  • After flashing, OpenBK access point configuration works at http://192.168.4.1/index, and PowerSave 1 can be added at startup for low-power mode after reboot.
Generated by the language model.
ADVERTISEMENT
Report a violation of the law
Reply Cool? Ranking DIY | New topic
Notify about new articles
📢 Listen (AI):
  • Hi,

    I have a new entry for the IoT device teardowns list for a 16A WIFI Mini Smart Switch.
    There are already several entries for similar devices like this one which can be bought at a very low price e.g. at https://de.aliexpress.com/item/1005005302988558.html
    However this one, which is distributed by vendor SHUNSHUN in Germany has a different layout, which makes it pretty easy to flash OpenBeken on it.

    Teardown:
    Mini Smart Switch with technical information and connection inputs. Image of the interior of a Mini Smart Switch 16A WIFI showing its electronic components. View of a disassembled Mini Smart Switch 16A WIFI, showing internal components and its casing. Close-up of a smart switch interior with a CB2S module and various electronic components. Close-up of the PCB inside a Mini Smart Switch 16A WIFI with visible UART connection pins.

    As shown on the uploaded image, we just need to connect 4 wires to an UART controller:
    Mini Smart Switch board with wires connected to a UART controller.

    TX1 -> UART RX
    RX1 -> UART TX
    GND -> UART GND
    3v3 -> UART 3V

    Reset for Flash Mode: Disconnect 3V shortly from UART and reconnect afterwards.
    Chip type: BK7231N
    Baud rate: 115200

    Connect WIFI to OpenBK Access Point and access for initial configuration:
    http://192.168.4.1/index

    Extracted device template (anonymized):
    JSON format:
    Code: JSON
    Log in, to see the code


    Text description:
    Device configuration, as extracted from Tuya:
    - Pair/Toggle All Button on P10
    - WiFi LED on P7
    - TglChannelToggle (channel 1) on P26
    - Relay (channel 1) on P8
    Device seems to be using CB2S module, which is using BK7231N.
    And the Tuya section starts, as usual, at 2023424

    In OpenBeken, type PowerSave 1 in Startup Command to activate low power mode after every reboot.

    Cool? Ranking DIY
    About Author
    OBeker
    Level 1  
    Offline 
    OBeker wrote 1 posts with rating 1. Been with us since 2024 year.
  • ADVERTISEMENT
  • #2 20970115
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14418
    Help: 650
    Rate: 12376
    And here is OBK template:
    Code: JSON
    Log in, to see the code

    Close-up view of the SHUNSHUN WiFi mini switch with electronic components on the circuit board.
    Helpful post? Buy me a coffee.
Reply Cool? Ranking DIY | New topic
Notify about new articles
📢 Listen (AI):
Report a violation of the law
Today's popular

FAQ

TL;DR: For anyone flashing a 16A Tuya-style relay, this SHUNSHUN switch exposes 4 UART wires and makes OpenBeken setup unusually simple; as the teardown notes, "we just need to connect 4 wires" to flash the BK7231N/CB2S board, then configure it at 192.168.4.1. [#20964525]

Why it matters: This FAQ gives a clean, citation-ready answer set for identifying pins, entering flash mode, and configuring OpenBeken on this exact mains smart switch.

Option Layout access for flashing Module/chip noted Flashing difficulty
SHUNSHUN 16A WIFI Mini Smart Switch UART pads are easy to reach; 4-wire hookup shown CB2S / BK7231N Easier
Similar low-cost Tuya mini switches Several related entries exist, but layout differs Not specified in this thread Harder or less convenient

Key insight: The biggest takeaway is layout, not just chipset. This SHUNSHUN variant is easier to flash because its board exposes a straightforward UART connection and a simple 3V3 reconnect method for flash mode. [#20964525]

Quick Facts

  • Rated model name: 16A WIFI Mini Smart Switch; the posted OpenBeken template identifies SHUNSHUN as vendor and BK7231N as the chip. [#20970115]
  • Flashing uses 4 UART connections: TX1, RX1, GND, and 3V3. That direct pad access is the practical reason this teardown matters. [#20964525]
  • Recommended serial speed is 115200 baud, and initial OpenBK setup starts from the device AP at 192.168.4.1/index. [#20964525]
  • Confirmed OpenBeken pin map: P8 relay, P7 WiFi LED, P10 pair/toggle-all button, P26 channel-1 toggle behavior. [#20970115]
  • The Tuya configuration area reportedly starts at flash address 2023424, a useful marker during teardown, backup, and template work. [#20964525]

How do I flash OpenBeken onto the SHUNSHUN 16A WIFI Mini Smart Switch using the UART pads on the board?

Flash it by wiring the board’s exposed UART pads to a UART adapter, then rebooting into flash mode and uploading OpenBeken. 1. Connect TX1, RX1, GND, and 3V3 to the adapter. 2. Briefly disconnect and reconnect 3V3 to enter flash mode. 3. Flash the BK7231N device at 115200 baud, then join the OpenBK AP for setup at 192.168.4.1/index. [#20964525]

What UART wiring do I need for the BK7231N-based 16A WIFI Mini Smart Switch, including TX1, RX1, GND, and 3V3?

Use a 4-wire UART connection. Connect TX1 on the switch to UART RX, RX1 to UART TX, GND to UART GND, and 3V3 to UART 3V. Keep the TX and RX lines crossed, not straight-through. The thread shows this exact mapping for the BK7231N-based board. [#20964525]

How do I put this CB2S/BK7231N smart switch into flash mode by reconnecting 3V3?

Put it into flash mode by power-cycling only the 3V3 UART supply line. 1. Disconnect the 3V3 wire briefly. 2. Reconnect 3V3 to the board. 3. Start the flashing process immediately after reconnection. The posted teardown describes this as the reset method for flash mode on this device. [#20964525]

What baud rate should I use when flashing the SHUNSHUN 16A WIFI Mini Smart Switch with OpenBeken?

Use 115200 baud. That is the only flashing speed explicitly listed in the teardown notes for this SHUNSHUN 16A WIFI Mini Smart Switch with a BK7231N chip. Using the stated rate avoids guesswork during UART flashing. [#20964525]

How do I connect to the OpenBK access point and open the initial configuration page at 192.168.4.1?

After flashing, join the device’s OpenBK Wi-Fi access point and open 192.168.4.1/index in a browser. That page is the initial configuration interface mentioned in the thread. It is the first step for assigning pins, commands, and startup settings after the firmware boots. [#20964525]

What pin mapping should I use in OpenBeken for the SHUNSHUN 16A WIFI Mini Smart Switch, including the relay, WiFi LED, and button?

Use P8 = Relay, P7 = WiFi LED, P10 = Pair/Toggle All button, and P26 = channel-1 toggle behavior. The OpenBeken template maps them as Rel;1, WifiLED_n;0, Btn_Tgl_All;0, and TglChanOnTgl;1. This is the clearest pin assignment posted for this exact model. [#20970115]

What is the CB2S module in Tuya-based smart switches, and how does it relate to the BK7231N chip?

"CB2S is a Tuya Wi‑Fi module that hosts the device’s wireless MCU, defining the board family used in many compact smart switches." In this switch, the thread says the device uses a CB2S module, and that module is based on the BK7231N chip. In practice, CB2S is the module name and BK7231N is the underlying chip family. [#20964525]

What is OpenBeken, and why would someone install it on a Tuya-based 16A WiFi mini smart switch?

OpenBeken is replacement firmware used here to take control of the switch’s BK7231N hardware and configure it locally. The thread shows a full OpenBeken template for this 16A SHUNSHUN model and directs users to the OpenBK access point at 192.168.4.1/index for setup. People install it here because this board layout makes flashing unusually straightforward. [#20964525]

How does this SHUNSHUN 16A WIFI Mini Smart Switch layout compare with other similar low-cost Tuya switches for OpenBeken flashing?

This SHUNSHUN layout is easier to work with than several similar low-cost Tuya switches listed elsewhere. The author says there are already several related teardown entries, but this board has a different layout that makes OpenBeken flashing “pretty easy.” The main difference is accessible UART wiring rather than a different firmware process. [#20964525]

Why is this particular SHUNSHUN smart switch considered easier to flash than other similar devices?

It is easier to flash because the board exposes a simple UART hookup with only 4 wires and a basic 3V3 reconnect reset method. The author explicitly highlights the different layout as the reason it is “pretty easy” to flash with OpenBeken. Easier physical access reduces the hardest part of many teardowns: finding workable serial pads. [#20964525]

Where does the Tuya configuration section start in flash memory for this device, and why does that address matter during teardown or firmware work?

The Tuya configuration section starts at flash address 2023424. That address matters because it tells you where device-specific settings begin, which helps during teardown analysis, template extraction, or when comparing vendor configuration against an OpenBeken pin map. It is a useful reference point when reading or documenting the original firmware layout. [#20964525]

How do I extract and convert a Tuya device configuration JSON into an OpenBeken template for a BK7231N device?

Extract the Tuya JSON, identify the functional pins, then rewrite those functions into OpenBeken pin names. In this case, the extracted data points to P10 button, P7 WiFi LED, P26 toggle input, and P8 relay, and those values were converted into a finished OpenBeken template for a BK7231N / CB2S device. The posted template is the conversion result. [#20970115]

Why would the extracted Tuya JSON look partially malformed or anonymized, and which fields are still useful for identifying pins and features?

It can look malformed because the posted JSON was explicitly labeled “anonymized” and contains broken-looking fragments such as dns_prio merging into other fields. The useful parts still include the module name CB2S, chip family clues, and pin-related entries like onoff1 = 26, rl1_pin = 8, netled1_pin = 7, and total_bt_pin = 10. Those fields are enough to map core functions. [#20964525]

How do I enable low power mode in OpenBeken with the Startup Command 'PowerSave 1', and what effect does it have after reboot?

Enable it by entering PowerSave 1 in the OpenBeken Startup Command field. The thread states this activates low power mode after every reboot. That means the setting is intended to persist as a startup action rather than requiring manual entry each time the switch restarts. [#20964525]

What safety precautions should I follow when opening and flashing a mains-powered 16A WiFi smart switch over UART?

Treat it as a mains device and only work from the 3V3 UART side when the housing is open. Use the shown low-voltage connections only: TX1, RX1, GND, and 3V3. A practical failure case is miswiring TX/RX or repeatedly reconnecting the wrong lead instead of 3V3, which can prevent flashing and confuse boot behavior. [#20964525]
Generated by the language model.
ADVERTISEMENT