AX5721支持的反馈类型为： EnDat 2.2, BiSS C
参考链接：https://infosys.beckhoff.com/content/1033/ax5000_system_doku_hw2/18014401916712715.html?id=1304023088454547552
具体接线参考链接:
https://infosys.beckhoff.com/content/1033/ax5000_system_doku_hw2/9007202662392203.html?id=355591975281348722
