Meridian America 21 Benutzerhandbuch
3
C h a r a c t e r i s t i c s
Functional
The Analog Line Card contains an 8050 microprocessor that provides the
following functions:
following functions:
card self-identification
self-test
control card operation
status report to the controller
diagnostics for maintenance purposes
The Analog Line Card also provides the following:
. .
balanced terminating impedance
analog-to-digital and digital-to-analog conversion of transmission and
reception signals for 16 audio phone lines
reception signals for 16 audio phone lines
transmission and reception of SSD signalling messages over a
signalling channel in A10 format
signalling channel in A10 format
- -
detection of on-hook/off-hook status
connection of 20 Hz ringing signal and automatic disconnection when
the station goes
synchronization for connecting and disconnecting the ringing signal to
zero crossing of ringing voltage
zero crossing of ringing voltage
of SSD messages and PCM signals for diagnostic purposes
indication of board status with faceplate-mounted LED
correct initialization of all features at power-up
direct reporting of digit dialed (500 sets) by collecting dial pulses
Analog line card description
553-3001-l 61