CMX868E2 View Datasheet(PDF) - MX-COM Inc
Part Name
Description
MFG CO.
'CMX868E2' PDF : 43 Pages View PDF
Low Power V.22bis Modem
24
CMX868 Advance Information
Rx Mode Register b8: Rx Auto-equalize (DPSK/QAM modem modes)
This bit controls the operation of the receive DPSK/QAM auto-equalizer. Set to 0 in FSK
modes.
Bit 8 = 1
Enable auto-equalizer
Bit 8 = 0
DPSK mode: Auto-equalizer disabled
QAM mode : Auto-equalizer settings frozen
Rx Mode Register b7-6: Rx Scrambler (DPSK/QAM modem modes)
These 2 bits control the operation of the Rx de-scrambler used in QAM and DPSK
modes. Set both bits to 0 in FSK modes
Bit 7
Bit 6
1
1
De-scrambler enabled, 64 ones detect circuit enabled (normal use)
1
0
De-scrambler enabled, 64 ones detect circuit disabled
0
x
De-scrambler disabled
Rx Mode Register b5-3: Rx USART Setting (QAM, DPSK, FSK modem modes)
These three bits select the Rx USART operating mode. The 1% and 2.3% over-speed options
apply to DPSK/QAM modes only.
b5
b4
b3
1
1
1 Rx Synchronous mode
1
1
0 Rx Start-stop mode, no over-speed
1
0
1 Rx Start-stop mode, +1% over-speed (1 in 8 missing Stop bits allowed)
1
0
0 Rx Start-stop mode, +2.3% over-speed (1 in 4 missing Stop bits
allowed)
0
x
x Rx USART function disabled
Rx Mode Register b2-0: Rx Data bits and parity (QAM, DPSK, FSK Start-Stop modem modes)
In Start-stop mode these three bits select the number of data bits (plus any parity bit) in each received
character. These bits are ignored in Synchronous mode.
Bit 2 Bit 1 Bit 0
1
1
1 8 data bits + parity
1
1
0 8 data bits
1
0
1 7 data bits + parity
1
0
0 7 data bits
0
1
1 6 data bits + parity
0
1
0 6 data bits
0
0
1 5 data bits + parity
0
0
0 5 data bits
Rx Mode Register b2-0: Tones Detect mode
In Tones Detect Mode (Rx Mode Register b15-12 = 0001) b8-3 should be set to 000000
Bits 2-0 select the detector type.
Bit 2 Bit 1 Bit 0
1
0
0 Programmable Tone Pair Detect
0
1
1 Call Progress Detect
0
1
0 2100, 2225Hz Answer Tone Detect
0
0
1 DTMF Detect
0
0
0 Disabled
¤2001 MX-COM, Inc.
www.mxcom.com tel: 800 638 5577 336 744 5050 fax: 336 744 5054
Doc. # 20480205.007
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
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