Silicon Laboratories SI2493/57/34/15/04 - Manual (Page 146)

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146 Rev. 1.3
6.2.2.3. Special Requirements for India
To output a 0 dBm sine wave, use the following commands:
AT:PF800, C4DD, 7B5C, 595F
AT*Y254:W50, 0, 5B86,1
AT:U46,0
AT*Y1X1DT1
This command string turns off the high-frequency DTMF tone, leaving only the low-frequency DTMF tone when an
ATDT is sent. The tone is output continuously until any key is pressed. To restart the tone output, type AT*Y1DT1.
To change the tone power level, type ATU46,00X0 (where X is a hexadecimal value 0–F representing output power
in –1 dBm steps from 0 to –15 dBm).
Table 92. Dial Registers
Register Value Function
Pulse Dial Control
U37–U40 Pulse per Digit Definition
U42 PDBT Pulse Dial Break Time
U43 PDMT Pulse Dial Make Time
U45 PDIT Pulse Dial Interdigit Time
DTMF Control
U46 DTPL DTMF Power Level (and
Twist)
U47 DTNT DTMF On Time
U48 DTFT DTMF Off Time
Table 93. Line Interface/Control Registers
Register Bit Value Function
U4D 10 CLPD Check Loop Current Before
Dialing
1 LLC Low Loop Current Detect
(set for legacy TBR21)
0 LCN Loop Current Needed
U50 LCDN Loop Current Debounce
On Time
U51 LCDF Loop Current Debounce
Off Time
U52 XMTL Transmit Level
U67:
13:12
MINI
9 ILIM
7 DCR DC Impedance Select
6 OHS On-Hook Speed
3:2 DCV DC Termination Select
1 RZ Ringer Impedance
0 RT Ringer Threshold Select
U68 2 BTE Billing Tone Protect Enable
1 ROV Receive Overload
0 BTD Billing Tone Detected