The selected function for the GP3/MCLR pin is input, and you must enable the global weak-pullup bit in the microcontroller's configuration word.

GP3/MCLR管脚的 可选功能为输入，在微处理器配置命令中，必须使能全局弱上拉位。

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The reigning GP3 champion is expected to take part in Friday practice sessions next season.

CNN: Williams keep Maldonado for 2012

The 19-year-old won this season's inaugural GP3 series and has impressed Sauber after spending the campaign with the Swiss team as an affiliated driver.

BBC: Jerome D'Ambrosio & Esteban Gutierrez win F1 test roles