Sonoff S61

Sonoff’s Beken smart plug, sold as the S61S (iPlug Gen2, Matter over Wi-Fi), model S61STPF for the European plug. The firmware calls itself S61: its eWeLink model is SN-BK7238-S61-01, its board id FWSW-01-S61-BK, and the module is the WBBK_01P_V1.3. This folder holds or links everything specific to the S61; the tooling it shares with other Beken plugs is in tools/beken/, and the emulation that worked all of this out is described in docs/beken-s61-emulation.md.


Chip	BK7238 (ARM968E-S), 4 MB flash
Relay	P26
Button	P9, active low, pull-up
Relay LED, Wi-Fi LED	P0, P1, both lit low
Power meter	BL0937: CF P8, CF1 P6, SEL P24; 1 mΩ shunt, 2040:1 divider
Stock stores	EasyFlash V4 at `0x3e2000` (Wi-Fi, `elecCalibCoef`) and `0x3f6000`; never written by a conversion
Stock bootloader table	app `0x11000`, download slot `0x286000` (where it applies an rt_ota update), radio calibration `0x3e0000`

OpenBeken: drv_autoflash_sonoff_s61.c, the S61’s table for the tool’s OpenBeken driver (tools/beken/openbeken/drv_autoflash.c), which reads the stock Wi-Fi and meter calibration on first boot and applies the wiring; the build recipe, the 4 MB table and reverting to stock: openbeken.md. The 4 MB patches offered upstream are tools/beken/openbeken/.
ESPHome (LibreTiny): esphome.yaml, the path converted plugs name as their package_import_url; how it differs from the S60’s, the build, the reversion and what the emulator validated: esphome.md.
Stock firmware: the public dump upstream BekenEmulator publishes is what the emulator and its tests run; this repository holds no Sonoff firmware (tools/beken/emulator/).
The images the tool installs: OpenBeken with the driver and the 4 MB table (artifacts/openbeken-sonoff-s61-<version>.rbl) and ESPHome (artifacts/esphome-sonoff-s61-<version>.rbl), built and pinned by tools/repo/update_firmware.py (docs/updating-firmware.md).
The conversion tool’s route: tools/autoflash/routes/beken/
- the push through eWeLink from Sonoff’s firmware, OpenBeken and ESPHome each taking the next firmware as an update of its own, Sonoff’s firmware back from the public dump, the backup through OpenBeken’s flash reads after the first conversion (a run to ESPHome installs OpenBeken first, as the interim firmware, to take it). The route has run end to end in the emulator in every direction, faults and all (its fault suite); it has never yet run on a real plug. From Sonoff’s firmware a run to OpenBeken is B1, B2 (sent through eWeLink), K1, B4; a run to ESPHome is B1, B2 (OpenBeken as the interim firmware), J1, B4 (the backup through it), J2 (it fetches ESPHome), K2. A run back to Sonoff’s firmware ends with K3: eWeLink shows the plug online, and it answers there.