TN789 circuit pack is an interface between a DEFINITY system and
2 Wireless Fixed Base (WFB) radio units for the DEFINITY wireless
business system R1-PWT.
TN789 contains a main processor to handle data line circuit (DLC)
and upper medium access (MAC) layers of firmware.
TN789 also contains 2 lower MAC processors; 1 for each radio interface.
Each radio interface is referred to as an I2 interface.
I2 link is the connection between the Radio Controller (RC) and
the WFB. The RC supports up to two I2 links, each link consisting
of 4 pairs of twisted-pair cable: the transmit pair, the receive
pair, and the local power pair.
transmit pair transfers WFB control and frame information from
the RC to the WFB.
receive pair transfers status and frame information from the WFB
to the RC. If the RC cannot provide power to the WFB, a third
pair (to the WFB) can supply local power. When possible, the transmit
pair and the receive pair provide phantom power from the RC to
circuit pack includes a standard TDM bus interface from a system,
2 radio interfaces to 2 separate radio units, and 2 synchronization
addition, 2 RS-232 interfaces provide for a debug terminal and
for setting up the wireless terminal. Provides an interface to
Wizard II base stations (DWBS).