Custom firmware for Sonoff ZBMINI (01MINIZB) and eWeLink Switch ZR-02

ITead offers a new model of small one- and two-way switches. These devices are based on the modern and powerful CC2652P1F chip. This chip has a built-in amplifier and should provide excellent signal strength and connection range. But real applications show that is not true.

The PTVO firmware works perfectly on with chip on the corresponding modules from EBYTE E72-2G4M20S1E. So, we supposed to get similar results from ZBMINI and get a good router for an appropriate price. But real tests disappointed. The device didn’t start with the firmware for CC2652P at all, but successfully works when you select the CC2652R chip type in the configurator.

Initially, I’ve suspected a bug in the firmware and double-checked everything. But a colleague compared recommended and real schematics for this chip. Some important components are missed on a PCB! I suppose, ITead “optimized” a PCB to use any version of the CC2652 chip on this PCB. Currently, the whole industry has problems with production of chips and manufacturers should use the current offer on the market and change components by the objective situation.

1. So, we’ll never get the best performance from this device.
2. The next lot may have another version of the CC2652 chip.

Here is the similar switch with the same “optimization”. Z2M detects it as eWeLink Switch ZR-02. It has a good quality/price value for the CC2652P module. You can unsolder a small PCB with the CC2652P chip from the box and use it in your DIY project because this PCB has all necessary pins for programming and small DIY projects. The main disadvantage: you need the cJTAG-compatible flasher (XDS110 or J-Link V11). The original firmware does not have serial bootloader.