FAQ
TL;DR: Teckin SP23’s RTL8710BN module boots with a 40 MHz crystal and logs "TUYA IOT SDK V:2.0.0"; validate via UART before any ESP swap or OBK flash. [Elektroda, divadiow, post #21376313]
Why it matters: This FAQ helps tinkerers decide whether to replace or reflash RTL8710BN-based T112_V1.1 boards in Teckin SP23 plugs.
Quick Facts
- Not a drop-in ESP-02S swap; pinout differs and the module is slightly wider, so short wires may be needed. [Elektroda, ferbulous, post #20836499]
- UART boot shows 40 MHz XTAL and a 2 MB flash layout ("8710_2M") under Tuya firmware. [Elektroda, divadiow, post #21376313]
- OBK template exists for an RTL8710B plug: BL0937 CF/CF1/SEL, relay, button, inverted LED; status: work in progress. [Elektroda, divadiow, post #21381177]
- Dev note: Realtek branch stalled after a bricked module; module-only samples can unblock work. [Elektroda, p.kaczmarek2, post #20836819]
- Desoldering tip: use flux, moderate iron temperature, and keep the tip clean for best results. [Elektroda, p.kaczmarek2, post #20838328]
Is the T112_V1.1 (RTL8710BN) pin-compatible with ESP-02S or TYWE2S?
No. It is not a drop-in for ESP-02S. The pinout differs and the module is slightly wider. Expect to add short jumper wires or use an adapter. That makes straight swapping risky on compact PCBs. [Elektroda, ferbulous, post #20836499]
What board and SoC are inside the Teckin SP23 discussed here?
The SP23 PCB is marked HYS-01-127_V1.1, dated 2018-10-16. The Wi‑Fi module uses Realtek RTL8710BN. UART boot logs show a 40 MHz crystal and a 2 MB flash configuration, under Tuya firmware. Photos and dumps confirm this setup. [Elektroda, divadiow, post #21376313]
What UART settings work to read boot logs from RTL8710BN in this plug?
Hook GND, TX, and RX to the module’s UART test points. The Tuya boot logs indicate a 9600 bps serial rate. The banner also shows the 40 MHz XTAL. Use these cues to confirm a stable connection before any flashing. [Elektroda, divadiow, post #21376313]
Is there an OpenBeken (OBK) template for this RTL8710B-based plug?
Yes. A shared OBK template maps BL0937 CF, CF1, and SEL, plus relay, button, and an inverted LED. It targets a board labeled T102_V1.1. The author notes the firmware is "work in progress." [Elektroda, divadiow, post #21381177]
How should I desolder the module without lifting pads?
Use ample flux, moderate iron temperature, and keep the tip clean. Preheat the area and wick solder gradually. "Remember that flux is crucial for this process." Avoid prying under the metal can to protect pads. [Elektroda, p.kaczmarek2, post #20838328]
I ripped a pad during removal. Can I still recover the board?
Often yes. You can regenerate a pad and reconnect using a fine wire to the trace. In the thread, a module with one ripped pad was still considered salvageable by the developer. Proceed carefully after continuity checks. [Elektroda, p.kaczmarek2, post #20840128]
Does OBK plan to support RTL8720C as well?
Support was asked, but no confirmation appears here. The developer said the Realtek branch stalled after a module was bricked. Progress depends on obtaining a working module to resume development. [Elektroda, p.kaczmarek2, post #20836819]
Where can I get a T112_V1.1 or similar RTL8710BN module?
Participants pulled modules from Teckin SP23 smart plugs bought on eBay. No standalone module source was identified in this thread. Some threads mention TYWE2S, but that does not provide a direct module supplier. [Elektroda, divadiow, post #20836811]
Are TYWE2S drop-in replacements for the module in this SP23?
Some Teckin discussions mention TYWE2S compatibility. However, this unit was not like‑for‑like. Plan for rewiring and confirm the footprint width before committing. Direct swaps may not align mechanically. [Elektroda, divadiow, post #20836811]
Can I back up the original Tuya firmware before flashing?
Yes. The thread shares a full flash backup. Verify boot over UART first. Then make a dump and archive it safely.
- Connect UART and capture boot logs to confirm stable operation.
- Attach an SPI programmer or clip and read the flash to a file.
- Verify the dump integrity and store it offline. [Elektroda, divadiow, post #21376313]
Which pins control relay, LED, and button under OBK on this build?
Template mapping shows Relay on GPIO10, Button on GPIO11, and an inverted LED on GPIO1. BL0937 energy metering uses CF on GPIO0, CF1 on GPIO8, and SEL on GPIO9. Adjust if your PCB wiring differs. [Elektroda, divadiow, post #21381177]
Should I replace the module with an ESP or keep RTL8710BN and flash OBK?
Keeping RTL8710B avoids footprint mismatches and preserves power‑meter wiring. The OBK route already has a published template and ongoing work. Validate your pins against the template, then proceed with software changes rather than hardware swaps. [Elektroda, divadiow, post #21381177]
What boot or Wi‑Fi behaviors should I expect from Tuya RTL8710BN firmware?
Expect OTA partition selection logs and LwIP DHCP stop messages during mode switches. The log can repeat Wi‑Fi init and report “not find scan ssid” for tuya_mdev_test1. The banner shows boot reason 0 and calibration results. [Elektroda, divadiow, post #21376313]
