# UART

**Serial Ports** (all mapped to the corresponding number, IE T4 R4 is Serial\_4)

1. Purple, Designated for the CM4 telemetry link using a male to male jumper. 
2. Brown, Designated for an external GPS, located next to I2C.
3. Blue, Free use
4. Orange, Free use
5. White, Serial 5 is shared with SBus in. If you are using a SBus Rx then Serial 5 is unavailable.

<figure><img src="/files/21z2kyvYnorOYQwnZWZ6" alt=""><figcaption></figcaption></figure>


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