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README.md

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 # RT-Thread #
 
 [![Build Status](https://travis-ci.org/RT-Thread/rt-thread.svg)](https://travis-ci.org/RT-Thread/rt-thread)
-[![Gitter](https://badges.gitter.im/Join Chat.svg)](https://gitter.im/RT-Thread/rt-thread?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+[![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/RT-Thread/rt-thread?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
 RT-Thread is an open source real-time operating system for embedded devices from China, which has strong scalability: from a tiny kernel running on a tiny core, for example ARM Cortex-M0, or Cortex-M3/4/7, to a rich feature system running on ARM Cortex-A8, ARM Cortex-A9 DualCore etc.