Baseband Processor For Mixed Mode Land Mobile Radio
CMX880
Receiving and Decoding Selcall Tones
The CMX880 detects the Selcall tones that match the pre-programmed frequencies defined in the ‘RX SELCALL
TONES’ words (B1.12 to B1.27) of the ‘PROGRAMMING REGISTER’ ($C8). The tone bandwidth and signal
level threshold are set in the ‘SELCALL TONE BW AND LEVEL’ word of the ‘PROGRAMMING REGISTER’.
Table 3 lists the commonly used Selcall tones together with the values for programming the ‘RX SELCALL
TONES’ words. This does not preclude other tones being programmed. More details for programming Selcall
tones are provided in section 1.5.2.
Table 3 Selcall Tone Sets and Corresponding Rx Programming Codes
EIA
Tone Code
EEA
Tone Code
CCIR
Tone Code
Tone
Address
Freq.
(Hz)
Freq.
(Hz)
Freq.
(Hz)
(hex)
4226
42A6
4340
43C1
4441
44C2
4542
45C3
4643
46E0
47E1
48E2
4760
4861
41A7
-
(hex)
4741
4420
4461
44A2
4500
4542
45A1
4601
4661
46C2
43E0
4362
4840
43A1
47C0
48C1
(hex)
4741
4420
4461
44A2
4500
4542
45A1
4601
4661
46C2
48C1
4362
4840
43A1
47C0
43E0
0
1
2
3
4
5
6
7
8
600
741
882
1981
1124
1197
1275
1358
1446
1540
1640
1747
1860
1055
930
1981
1124
1197
1275
1358
1446
1540
1640
1747
1860
2400
930
1023
1164
1305
1446
1587
1728
1869
2151
2435
2010
2295
459
9
A (10)
B (11)
C (12)
D (13)
E (14)
F (15)
2247
991
2110
2400
2247
991
2110
1055
NoTone
ZVEI 1
ZVEI 2
Freq.
(Hz)
Tone Code
(hex)
Freq.
(Hz)
Tone Code
(hex)
0
1
2
3
4
5
6
7
8
2400
1060
1160
1270
1400
1530
1670
1830
2000
2200
2800
810
48C1
43E1
4441
44A2
4521
45A0
4620
46A3
4760
4802
4A41
42E6
4383
4340
4981
4280
2400
1060
1160
1270
1400
1530
1670
1830
2000
2200
885
48C1
43E1
4441
44A2
4521
45A0
4620
46A3
4760
4802
4340
42E6
42A6
4280
4383
4981
9
A (10)
B (11)
C (12)
D (13)
E (14)
F (15)
810
740
680
970
970
885
2600
680
2600
Selcall tones can be used to flag the start and end of a call. They may also occur during a call in which case the
tone will be audible at the receiver. If enabled, an interrupt will be issued when a signal matching a valid Selcall
ã 2001 Consumer Microcircuits Limited
17
D/880/1
CMLMICRO [ CML MICROCIRCUITS ]
