keil中左边的r1 r2 r3 r4是什么意思

\u6709\u56db\u4e2a\u7535\u963bR1\u3001R2\u3001R4\u3001R5\u90fd\u4e3a5\u6b27\u59c6\uff0c\u5de6\u8fb9\u662f5\u4f0f\uff0c\u53f3\u8fb9\u4e24\u7aef\u70b9\u95f44\u4f0f\uff0c\u6c42R3

40\u6b27\u59c6\u5427\uff01
\u5de6\u8fb9\u662f\u7535\u6e90 \u53f3\u8fb9\u662fR3\u7684\u7535\u538b\u3002 \u53ef\u4ee5\u770b\u4f5c\u6ca1\u6709R2\u548cR5. \u7b49\u6548\u4e8e\u6c42\u4e32\u8054\u7535\u8def\u4e2d\u6c42\u4e00\u4e2a\u7535\u963b\u7684\u963b\u503c\u3002

\u2235\u4e32\u8054\u7535\u8def\u7535\u963b\u8d8a\u4e32\u8d8a\u5927\u3001\u5927\u4e8e\u4efb\u4f55\u4e00\u4e2a\u5206\u7535\u963b\uff0c\u2234R1\u548cR3\u7ec4\u6210\u4e32\u8054\u7535\u8def\u7684\u603b\u7535\u963b\u5927\u4e8eR1\u963b\u503c\uff1b\u2235\u5e76\u8054\u7535\u8def\u7535\u963b\u8d8a\u5e76\u8d8a\u5c0f\u3001\u5c0f\u4e8e\u4efb\u4f55\u4e00\u4e2a\u5206\u7535\u963b\uff0c\u2234R2\u548cR4\u7ec4\u6210\u5e76\u8054\u7535\u8def\u7684\u603b\u7535\u963b\u5c0f\u4e8eR2\u7684\u963b\u503c\uff1b\u2235R1=R2\uff0c\u2234\u4e32\u8054\u7535\u8def\u7684\u603b\u7535\u963b\u4e00\u5b9a\u5927\u4e8e\u5e76\u8054\u7535\u8def\u7684\u603b\u7535\u963b\uff0e\u6545\u9009A\uff0e

是工作寄存器。

那是ARM内核的工作寄存器。
你需要阅读一下ARM的RTM，了解一下ARM架构的基础知识……

扩展阅读：北京旅行 ... missing before unsigned ... keil missing function ... error c187 not an lvalue ... warning c206 missing ... keil error c187 ... keil c51 ... missing before code ... cannot read rte data ...