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As indicated in the Figure - µC/TCP-IP Source Code, all the files in the Source folder must be added to your project tree. Furthermore, if a TCP-/IP port exists for your CPU architecture inside de Ports folder, you can also include it to your project files.
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\Micrium\Software\uC-TCPIP
\Micrium\Software\uC-TCPIP\Dev\WiFi\<device_name>
\Micrium\Software\uC-TCPIP\Dev\WiFi\Manager\Generic
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