# Micro USB

There are 2 micro USB ports on the board. 

(Red) is connected to the STM32F405 and used to flash firmware in DFU mode and as a telemetry connection under normal use.

(Purple) is used solely to flash the EMMC on the CM4. It is only connected when the DIP switch (1) is set to "ON".

<figure><img src="/files/kIGdbzaOCQ4C6e1pF68i" alt=""><figcaption></figcaption></figure>


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