Bt8960
Bt8960EVM Hardware User’s Guide
Bt8960EVM Hardware User’s Guide
Interface Descriptions
100188B
Conexant
7
Conexant Proprietary and Confidential
Interface Descriptions
Line Interface (J1, J2)
Connectors
Two connectors are included on the 8960 line card to provide connections to the
line. J1 is an RJ-45 style connector common to telecommunication equipment.
Only pins 4 (tip) and 5 (ring) are utilized on the connector. Pins 1, 2, 3, 6, 7 and 8
of J1 are left unconnected. J2, an all-purpose terminal strip connector, can also be
used to connect to the line tip and ring signals.
Prototyping Provisions
Test points and prototype space are included on the line card to facilitate the
testing of remote line powering and lightning protection circuits. See
determine which test points are provided for these purposes. In most cases, a 0
ohm resistor must be removed prior to adding the circuitry to be tested.
Power Supply/Line Card Configuration Interface (J3)
Power Supply (pins 1 and 2):
Power is provided to the line card through the J3 connector. Two test points are
provided so that power can be measured and/or supplied by an alternative source if
desired. If power is supplied though these test points, be sure to remove the mating
connector from J3 because the cable connected to J3 will create a short between
power and ground when the power switch on the power box is in the OFF position.
Two large capacitors (C11, C12) and a transorb (CR4) provide a steady 5 volt
power rail and protect circuits on the line card from dangerous transient power
spikes. The POWER LED (CR1) indicates when power is applied to the line card.
Remote/Local Unit Configuration (pin 3)
In addition to supplying the line card with 5 volts and ground, the 3-pin connector
also contains a control pin used by the 8032 microprocessor to indicate if the line
card is to be configured as the local (HTU-C/LTU) or remote (HTU-R/NTU) unit.
If pin three of J3 (J3-3) is connected to ground, the line card will be configured as
the local unit. Conversely, if J3 is left open, the line card will be configured as the
remote unit. Control of the local/remote configuration function can be removed
from the J3 connector and given to jumper J12 by removing the 0 ohm resistor,
R44, and installing jumper J12. Note that the 8032 microprocessor PORT1B7
signal (pin 9) contains an internal pull-up resistor that is connected to J3-3 so that
no external pull-up resistor is required.
