Which types of service cards can be inserted into the 4+1 slots of the IDM MINI8, and which on-site services do they connect to respectively?

The interfaces on the user side of the IDM MINI8 are provided by the service cards inserted into the slots. The voice card supports subscriber line (FXS) and trunk line (FXO) analog telephone interfaces, with a telephone audio range of 300 Hz to 3400 Hz and compression per A-law in ITU-T G.711; the magneto card suits the magneto telephones used in electric power, oilfield and mining sectors; the EM card provides 2-wire or 4-wire EM audio interfaces for audio trunks between switches; and the serial port card supports RS232/RS422/RS485 and carries low-speed data channels such as telecontrol, monitoring and acquisition. The four types of service cards do not have dedicated positions among the slots and can coexist in the same chassis; after multiplexing, the services use E1 transmission over one E1 line. The number of channels of each service card is determined by the card type; this is not yet recorded in the knowledge base.