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You need to ground RST, GPIO0 to start. after 3 seconds release RST. after another 3 seconds, release gpio0.
Flashing - Preparation
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)
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