CC254X system ID

在BLE 协议栈中有system ID，这个是干嘛用的？

 systemId[0] = ownAddress[0];
        systemId[1] = ownAddress[1];
        systemId[2] = ownAddress[2];

        // set middle bytes to zero
        systemId[4] = 0x00;
        systemId[3] = 0x00;

        // shift three bytes up
        systemId[7] = ownAddress[5];
        systemId[6] = ownAddress[4];
        systemId[5] = ownAddress[3];

systemId 的设置一定要按照这种格式吗？

system ID 就是mac address，可以更改。具体请看这边： https://www.deyisupport.com/question_answer/wireless_connectivity/bluetooth/f/103/t/62201.aspx

MAC地址是不是有多种？有出厂带的私有MAC，是固定且全球唯一的标识符。另外可以自定义MAC地址