The Cortex Microcontroller Software Interface Standard (CMSIS) is a vendor-independent hardware abstraction layer for the Cortex®-M processor series and defines generic tool interfaces. The CMSIS enables consistent device support and simple software interfaces to the processor and the peripherals, simplifying software re-use, reducing the learning curve for microcontroller developers, and reducing the time to market for new devices.

https://keilpack.azureedge.net/pack/ARM.CMSIS.5.6.0.pack

这个是ARM公司的官方keil5芯片支持包，适用于keil uv5,下载后双击安装即可

官网巨慢

ARM公司最新版官方库 ARM.CMSIS.5.6.0 ，支持所有cortex-m系列处理器，有需要的自行下载，双击安装即可