To learn anything, go to the official website.
Download the protocol stack of cc2541: http://www.ti.com/tool/BLE-STACK
After installing the protocol stack, open the file path:
All the materials are available. If you study cc2541, the materials you bring are enough. Regarding the osal system, the introduction of each layer protocol and the introduction of functions are very comprehensive. No need to blog to learn.
User manual: http://processors.wiki.ti.com/index.php/BLE_Device_Monitor_User_Guide
Software download: http://www.ti.com.cn/zh-cn/wireless-connectivity/simplelink-solutions/bluetooth-low-energy/design-development.html
