CMX808AE3 CML Microcircuits, CMX808AE3 Datasheet - Page 7

• Manufacturer Part Number: CMX808AE3
• Description: Family Radio CTCSS Type 2 Encoder and Decoder
• Manufacturer: CML Microcircuits

Family Radio CTCSS 'Type 2' Encoder and Decoder
1.5
The CMX808A is a programmable CTCSS ‘Type 2’ encoder and decoder for Family Radio, see Figure 1.
The receiver of the CMX808A decodes a user-programmable set of up to 7 tones with minimum software
intervention; the band-pass filter is designed to filter out the CTCSS sub-audio tones. A high resolution tone
encoder performs accurate generation of CTCSS tones.
Each function, and the routing of signals, is flexible and may be configured or controlled by the user's
software.
1.5.1
8-bit Write Only Registers
16-bit Write Only Registers
COMMAND
COMMAND
ADDRESS/
ADDRESS/
1999 Consumer Microcircuits Limited
HEX
HEX
$01
$80
$82
$83
$84
General Description
Software Description
Address/Commands
Instructions and data are transferred, via "C-BUS", in accordance with the timing information given in
Figure 4.
Instruction and data transactions to and from the CMX808A consist of an Address/Command (A/C)
byte which may be followed by either:
REGISTER
PROGRAM
PROGRAM
SUB-AUDIO
CTCSS RX
CTCSS RX
TX FREQ.
TX FREQ.
REGISTER
CONTROL
CONTROL
GENERAL
(Byte 1)
(Byte 2)
(Byte 1)
(Byte 2)
CTCSS
CTCSS
NAME
RESET
AUDIO
NAME
(i)
(ii)
NOTONE
CTCSS
ENABLE
ENABLE
TX BPF
BIT 7
BIT 7
BIT 7
(D7)
BIT 7
TX
(D7)
N/A
0
TX
a further instruction or data (1 or 2 bytes) or
a status or Rx data reply (1 byte)
CTCSS
DECODER
BIT 6
BIT 6
BIT6
MSB
ENABLE
ENABLE
BIT2
(D6)
RX BPF
CTCSS TONE ADDRESS
BIT 6
0
(D6)
N/A
BIT 5
BIT 5
BIT 5
BIT 1
(D5)
UN-MUTE
0
BIT 5
BIT 3
MSB
(D5)
BPF
N/A
CTCSS DECODER BANDWIDTH
7
CTCSS TX FREQUENCY
CTCSS FREQUENCY
BIT 12
BIT 4
BIT 4
BIT 4
BIT 0
MSB
(D4)
LSB
BIT 4
BIT 2
BIT 4
MSB
(D4)
N/A
BIT 11
BIT 11
BIT 3
BIT 3
BIT 3
MSB
(D3)
CTCSS TX FREQUENCY
BIT 3
BIT 1
BIT 3
(D3)
N/A
AUDIO ATTENUATION
CTCSS FREQUENCY
BIT 10
BIT 10
BIT 2
BIT 2
BIT 2
(D2)
BIT 2
BIT 0
BIT 2
(D2)
LSB
N/A
BIT 1
BIT 1
BIT 1
BIT 9
BIT 9
BIT 1
BIT 1
(D1)
(D1)
N/A
0
CTCSS
MASK
BIT 0
BIT 0
BIT 0
BIT 0
(D0)
BIT 0
BIT 8
BIT 8
IRQ
LSB
N/A
(D0)
LSB
LSB
CMX808A
D/808A/5