4-Level FSK Modem Data Pump
Page 2 of 50
MX929B PRELIMINARY INFORMATION
CONTENTS
Section
Page
1. Block Diagram............................................................................................................... 6
2. Signal List...................................................................................................................... 7
3. External Components................................................................................................... 8
4. General Description.................................................................................................... 10
4.1 Description of Blocks ....................................................................................................... 10
4.1.1 Data Bus Buffers................................................................................................................... 10
4.1.2 Address and R/W Decode .................................................................................................... 10
4.1.3 Status and Data Quality Registers........................................................................................ 10
4.1.4 Command, Mode, and Control Registers ............................................................................. 10
4.1.5 Data Buffer............................................................................................................................ 10
4.1.6 CRC Generator/Checker ...................................................................................................... 10
4.1.7 FEC Generator/Checker....................................................................................................... 10
4.1.8 Interleave/De-Interleave Buffer............................................................................................. 10
4.1.9 Frame Sync Detect ............................................................................................................... 10
4.1.10 Rx Input Amp ........................................................................................................................ 11
4.1.11 RRC Low Pass Filter............................................................................................................. 11
4.1.12 Tx Output Buffer ................................................................................................................... 12
4.1.13 Rx Level/Clock Extraction..................................................................................................... 13
4.1.14 Clock Oscillator and Dividers................................................................................................ 13
4.2 Modem - µC Interaction ................................................................................................... 13
4.3 Binary to Symbol Translation ........................................................................................... 14
4.4 Frame Structure............................................................................................................... 15
4.5 The Programmer's View .................................................................................................. 16
4.5.1 Data Block Buffer.................................................................................................................. 16
4.5.2 Command Register............................................................................................................... 17
4.5.2.1
4.5.2.2
4.5.2.3
4.5.2.4
4.5.2.5
4.5.2.6
4.5.2.7
4.5.2.8
4.5.2.9
4.5.2.10
4.5.2.11
4.5.2.12
4.5.2.13
4.5.2.14
4.5.2.15
Command Register B7: AQSC - Acquire Symbol Clock ............................................ 17
Command Register B6: AQLEV - Acquire Receive Signal Levels ............................. 17
Command Register B5: CRC .................................................................................... 17
Command Register B4: TXIMP - Tx Level/Impulse Shape........................................ 17
Command Register B3 - Reserved ............................................................................ 17
Command Register B2, B1, B0: TASK....................................................................... 18
NULL: No effect.......................................................................................................... 19
SFP: Search for Frame Preamble.............................................................................. 19
RHB: Read Header Block........................................................................................... 20
RILB: Read 'Intermediate' or 'Last' Block ................................................................... 20
SFS: Search for Frame Sync...................................................................................... 20
R4S: Read 4 Symbols ................................................................................................ 20
RSID: Read Station ID................................................................................................ 20
T24S: Transmit 24 Symbols....................................................................................... 21
THB: Transmit Header Block...................................................................................... 21
©2001 MX-COM, INC.
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Doc. # 20480171.003
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