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For Release 2 (version 1.1) to Release 3 or higher (version 1.3 or higher) follow the instructions under "Updating Firmware Over the Air" in the xPico Wi-Fi User Guide, available from http://www.lantronix.com/products/xpico-wi-fi/#tab-docs-downloads
For the SDK, click here
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xPico WiFi (load this file first)
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