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# Serial

The Manifold 5S has two serial ports usable when the Brain option is installed. One of the ports (SERIAL 2) can optionally use CTS/RTS hardware handshaking.

<figure><img src="/files/LRqzWflRxdUcBUdTX2Ql" alt=""><figcaption></figcaption></figure>

Pinout of the Serial connectors follow the Cerulean Sonar serial connector standard. See image below. "TX" means data comes out of the switch. "RX" means data goes into the switch.

<figure><img src="/files/gCWiW7JrxQvtdeJXrmzE" alt=""><figcaption></figcaption></figure>

CTS/RTS can be optionally connected to SERIAL 2's 2-pin JST connectors. Pin 1 is CTS, Pin 2 is RTS.


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