EV6120 Datasheet, PDF (21/28 Pages) CML Microcircuits – For CMX612 Product Evaluation

Evaluation Kit for CMX612
EV6120
1.6.3.5 BT, ETSI and Bellcore type 2 demonstration
See flowchart in CMX612 datasheet (application notes section) for more information.
In ‘Feature Phone’ mode, the local speech path is enabled and muted when a CAS tone is detected
(when the CMX612 DET output is set in tone alert mode, termed early mute). Also signals from the
line, e.g. CAS tone, will be taken from the Rx side of the 2 to 4 wire interface.
In ‘Adjunct Box’ mode, the link to an external telephone, socket J2, is muted when a valid CAS tone
has been received (when CMX612 IRQN pin goes low in tone alert mode, termed late mute).
If the EV6120 is linked to a PC, see section 1.6.2, the point at which muting occurs can be toggled
between early and late.
Counters record the number of times muting has occurred (M) and the number of times a valid CAS
tone has been detected (C). The counts are displayed on row 3 of the LCD.
DTMF digit ‘D’ is transmitted on to the phone line as an acknowledgement tone. If the EV6120 is
linked to a PC other DTMF digits can be sent as an acknowledgement. CLI message parameters are
displayed on the top two rows of the LCD.
Whilst the acknowledgement is being transmitted testpoint TP19, labelled CAS, will be HI. This 60mS
pulse can be fed back to a CLI simulator for CAS performance testing.
1.6.3.6 (Stuttered) Dial Tone detect Algorithm Demonstration.
This is a simplified demonstration of the algorithm running in continuous mode only. The constants
are fixed to default values and only the resulting dial or stuttered dial tone detect figures are shown.
When the ‘SEL’ button is pressed the demonstration will halt at the end of the current test cycle.
During the idle period between tests the LED marked ‘MW’ will indicate the result of the last test. i.e. if
a stuttered dial tone was detected the LED will be on and if a normal dial tone was detected the LED
will be off.
© 2000 Consumer Microcircuits Limited
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UM6120/1