CMX138 CML Microcircuits, CMX138 Datasheet - Page 47

• Manufacturer Part Number: CMX138
• Description: Audio Scrambler and Sub-Audio Signalling Processor
• Manufacturer: CML Microcircuits

Audio Scrambler and Sub-Audio Signalling Processor
b7 – b0
See Table 2. Selecting the ‘DCS turn-off tone (254)’ during DCS transmit will cause the DCS turn off tone
to be transmitted. CTCSS does not need to be enabled in the Mode Control register to receive the ‘DCS
turn off tone’.
If the Tone Clone
frequency in the range of valid tones, the received tone number will be reported in the Tone Status
register ($CC) and the CTCSS decoder detection bandwidth should be set to its lowest value (P2.1).
9.1.14 Tx In-band Tone - $C3 write
b15-11
b10-6
b5-0
9.1.15 Status – $C6 read
b15 IRQ
b14 reserved
b13 In-band Tone event
b12 reserved
b11 CTCSS event
b10 DCS event
b9
b8
b7
b6
b5
b4
© 2008 CML Microsystems Plc
15
IRQ
15
reserved
AuxADC Threshold change
reserved
reserved
reserved
reserved
14
Tx In-band tone
14
0
Sub-Audio Tone number (dec) 0
In-band Tone, see Table 5 In-band Tone in the Datasheet.
reserved, clear to '0'.
0.
Changes in the Status register will cause this bit to be set to 1 if the corresponding interrupt
mask bit is enabled. An interrupt request is issued on the IRQN pin when this bit is 1 and the
IRQ MASK bit (b15 of Interrupt Mask register, $CE) is set to 1.
The Tone Status register $CC should be read to determine the exact cause. Cleared to 0 in Tx.
A CTCSS code has been detected or ceased. The Tone Status register $CC should be read to
determine the exact cause. Cleared to 0 in Tx.
A DCS code has been detected or ceased. The Tone Status register $CC should be read to
determine the exact cause. Cleared to 0 in Tx.
AUX ADC signal has just gone above the high threshold or has just gone below the low
threshold The AuxADC data register $A9 should be read to determine the exact cause.
13
Rx in
13
TM
mode is selected this allows the device in Rx to non-predictively detect any CTCSS
12
12
0
11
Ctcss
11
10
0
DCS
10
1 to 83
84
101 to 183
184
200
201 to 251
252
253
254
255
9
0
9
0
8
0
Page 47
ADC
Aux
8
7
0
no tone
select DCS code 1 to 83
select User Defined DCS code
select DCS tone 1 to 83 inverted
select User Defined DCS code inverted
select Tone Clone™ mode
select CTCSS tone 1 to 51
select User Defined CTCSS tone
select XTCSS maintenance tone
select DCS turn-off tone
Invalid tone
7
0
6
0
6
0
5
0
5
0
4
0
4
0
3
0
3
0
0
2
2
0
D/138_FI1.0/5
1
0
1
0
CMX138
PRG
0
0
0