PSB4860 Datasheet, PDF (48/250 Pages) Siemens Semiconductor Group – Digital Answering Machine with Full Duplex Speakerphone SAM EC

PSB 4860
Functional Description
Table 19 CPT Detector Result
Register # of Bits Name
Comment
STATUS 1
CPT
CP tone currently detected [340 Hz; 640 Hz]
CPT is not affected by reading the status word. It is automatically reset when the unit is
disabled. Table 20 shows the control register for the CPT detector.
Table 20 CPT Detector Registers
Register # of Bits Name
Comment
CPTCTL 1
EN
Unit enable
CPTCTL 1
MD
Mode (cooked, raw)
CPTCTL 5
I1
Input signal selection
CPTMN 8
CPTMN 8
CPTMX 8
CPTMX 8
CPTDT 8
MINB
MING
MAXB
MAXG
DIFB
Minimum time of a signal burst (t_Bmin)
Minimum time of a signal gap (t_Gmin)
Maximum time of a signal burst (t_Bmax)
Maximum time of a signal gap (t_Gmax)
Maximum difference between consecutive bursts
CPTDT 8
DIFG
Maximum difference between consecutive gaps
CPTTR 3
NUM
Number of cycles (cooked mode), 0 (raw mode)
CPTTR 8
MIN
Minimum signal level to detect tones
CPTTR 4
SN
Minimal signal-to-noise ratio
If any condition is violated during a sequence of cycles the timing checker is reset and
restarts with the next valid burst.
Note: In cooked mode CPT is set with the first burst after the programmed number of
cycles has been detected.
Note: The number of cycles must be set to zero in raw mode.
Semiconductor Group
48
10.97