Update README.md

README.md

@@ -5,11 +5,11 @@
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-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.
+RT-Thread is an open source IoT operating system 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 MIPS32, ARM Cortex-A8, ARM Cortex-A9 DualCore etc.
 
 ## Overview ##
 
-RT-Thread RTOS like a traditional real-time operating system. The kernel has real-time multi-task scheduling, semaphore, mutex, mail box, message queue etc. However, it has three different things:
+RT-Thread RTOS like a traditional real-time operating system. The kernel has real-time multi-task scheduling, semaphore, mutex, mail box, message queue, signal etc. However, it has three different things:
 
 * Device Driver;
 * Component;
@@ -30,8 +30,11 @@ RT-Thread RTOS can support many architectures:
 * ARM Cortex-R4
 * ARM Cortex-A8/A9
 * ARM920T/ARM926 etc
-* MIPS 
+* MIPS32
 * x86
+* Andes
+* C-Sky
+* RISC-V
 * PowerPC
 
 ## License ##