建立工程，成功创建两个虚拟串口

source/rt_thread/libcpu/risc-v/k210/tick.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2018/10/28     Bernard      The unify RISC-V porting code.
+ */
+
+#ifndef TICK_H__
+#define TICK_H__
+
+int tick_isr(void);
+int rt_hw_tick_init(void);
+
+#endif