给出了华为GSM/GPRS模块的指令集，和对应该模块的推荐流程，包括呼叫，短消息，内置和外置PPP拨号上网-Given Huawei GSM/GPRS module instruction set, and the process should be the recommendation of modules, including calls, text messages, internal and external dial-up PPP

详细研究了GPRS终端拨号上网连接认证注册的全过程，KDH格式，请使用CAJViewer打开-Detailed study the GPRS terminal dial-up Internet connection certified registered, KDH format, use CAJViewer open