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Document Supported USB Serial chips #13

Open unaiur opened 2 years ago

unaiur commented 2 years ago

I spend several days trying to flash a TLSR8253 board with a broken firmware using several USB serial bridges with different chips: Silabs CP2102, FTDI ft232 and Microchip MCP2200. And none worked.

I have had to repurpose a CH340G from a ESP32 board to be able to update the firmware on a TLSR8253 board. It worked the first time.

I think it will be worth adding a note to the webpage saying the USB serial chips that work.

pvvx commented 2 years ago

Only Chinese chips work. This was reported in profile topics... The reason is related to the internal organization of synchronization in the chips. On FTDI or other chips, it is impossible to build a continuous sequence of pulses with the intervals specified for the diagram. At high speeds, the CH340 also has gaps in the output of TX signals that are multiples of the volume of the internal buffer. To receive a signal from the Telink Swire bus, chips that use several points to check the signal value and advanced error handling of the UART frame with their rejection are also not suitable.