Flashing Notes from Net

It seems that some people have had luck flashing by:

OTA update using TuyaConvert for older versions of this dimmer
Flashing using a USB/serial board with the following connections
- Vcc - 3.3V
- TX - RX
- RX - TX
- GND - GND

Make sure to ground GPIO0 during boot.

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BYD - BF7612AM28T W9He

BF7612AMXXE-CN-MCU-Datasheet

TO TRY:

When flashing:

You need to ground RST, GPIO0 to start. after 3 seconds release RST. after another 3 seconds, release gpio0.

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- GPIO-0 - GND

Cutting the RX/TX lines on the MCU board and flashing with the above connections.
Disabling the MCU (disable the chip using it's NRST/RST (Reset) pin if available) and flashing
Desoldering the TYWE3S board and flashing

Flashing - Disabling the MCU

To boot the TYWE3S in flashing mode, GPIO0 needs to be connected to GND while powering up. It can be left grounded for the entire process. Flashing a TYWE3S connected to a MCU is a bit trickier than one without MCU. This is due the same Rx Tx pins used by MCU and serial programmer for flashing. The TYWE3S cannot be booted to flash mode with MCU sending data over the same pins. To be able to do that, we need to disable MCU from sending data over Rx and Tx pins. There are few ways to do it:1. Disconnect TYWE3S module from the rest of board. (Naah, too much work) 2. Just break the Rx track from MCU to TYWE3S, flash and then reconnect. (Messy work, we want cleaner approach) 3. Just keep MCU disabled while flashing TYWE3S without any soldering / cutting. (We like that)

The easiest is to keep Keep MCU disabled is by identifying the NRST/RST (Reset) pin of the MCU from its datasheet and connect it to GND for the entire flashing process. This will keep MCU disabled while you flash TYWE3S. If there are some contacts or test points in switches that connect to the MCU, you might be lucky to find contacts for RST that you can easily solder onto.