User ManualTable of ContentsTable of Contents3List of Figures7List of Tables91.0 System Overview111.1 Functional Summary111.1.1 Transmit Section131.1.2 Receive Section131.1.3 Timing Recovery and Clock Interface131.1.4 Microcomputer Interface141.1.5 Test and Diagnostic Interface (JTAG)141.2 Applications151.2.1 Voice/Data Pairgain151.2.2 Internet Connectivity Transport161.2.3 ISDN Basic Rate Interface Concentrator171.3 Pin Descriptions182.0 Functional Description252.1 Transmit Section252.1.1 Symbol Source Selector/Scrambler262.1.2 Variable Gain Digital-to-Analog Converter282.1.3 Pulse-Shaping Filter282.1.4 Line Driver282.2 Receive Section292.2.1 Variable Gain Amplifier292.2.2 Analog-to-Digital Converter302.2.3 Digital Signal Processor302.2.3.1 Digital Front-End312.2.3.2 Offset Adjustment322.2.3.3 DC Level Meter322.2.3.4 Signal Level Meter322.2.3.5 Overflow Detection a...322.2.3.6 Far-End Level Meter322.2.3.7 Far-End Level Alarm322.2.4 Echo Canceler332.2.4.1 Linear Echo Canceler (LEC)332.2.4.2 Nonlinear Echo Canceler (NEC)332.2.5 Equalizer332.2.5.1 Digital Automatic Gain Control...332.2.5.2 Feed Forward Equalizer (FFE)342.2.5.3 Error Predictor (EP)342.2.5.4 Decision Feedback Equalizer 2....342.2.5.5 Microcoding342.2.6 Detector342.2.6.1 Slicer342.2.6.2 Peak Detector (PKD)352.2.6.3 Error Signals352.2.6.4 Scrambler Module352.2.6.5 Sync Detector362.2.6.6 Detector Meters362.3 Timing Recovery and Clock Interface382.3.0.7 Timing Recovery Circuit392.3.0.8 Crystal Amplifier392.4 Channel Unit Interface402.5 Microcomputer Interface422.5.1 Source Code422.5.2 Microcomputer Read/Write422.5.2.1 RAM Access Registers432.5.2.2 Multiplexed Address/Data Bus432.5.2.3 Separated Address/ D...432.5.3 Interrupt Request432.5.4 Reset442.5.5 Registers442.5.6 Timers442.6 Test and Diagnostic Interface (JTAG)463.0 Registers473.1 Conventions473.2 Register Summary483.2.1 0x00—Global Modes and Status Register (glo...543.2.2 0x01—Serial Monitor Source Select Register...543.2.3 0x02—Interrupt Mask Register Low (mask_low...553.2.4 0x03—Interrupt Mask Register High (mask_hi...563.2.5 0x04—Timer Source Register (timer_source)563.2.6 0x05—IRQ Source Register (irq_source)573.2.7 0x06—Channel Unit Interface Modes Register...573.2.8 0x07—Receive Phase Select Register (receiv...583.2.9 0x08—Linear Echo Canceller Modes Register ...583.2.10 0x09—Nonlinear Echo Canceller Modes Regis...593.2.11 0x0A—Decision Feedback Equalizer Modes Re...603.2.12 0x0B—Transmitter Modes Register (transmit...603.2.13 0x0C—Timer Restart Register (timer_restar...623.2.14 0x0D—Timer Enable Register (timer_enable)...623.2.15 0x0E—Timer Continuous Mode Register (time...633.2.16 0x0F—Test Register (reserved2)633.2.17 0x10, 0x11—Startup Timer 1 Interval Regis...633.2.18 0x12, 0x13—Startup Timer 2 Interval Regis...633.2.19 0x14, 0x15—Startup Timer 3 Interval Regis...633.2.20 0x16, 0x17—Startup Timer 4 Interval Regis...633.2.21 0x18, 0x19—Meter Timer Interval Register ...633.2.22 0x20—Test Register (reserved9)643.2.23 0x1A, 0x1B—SNR Alarm Timer Interval Regis...643.2.24 0x1C, 0x1D—General Purpose Timer 3 Interv...643.2.25 0x1E, 0x1F—General Purpose Timer 4 Interv...643.2.26 0x21—ADC Control Register (adc_control)653.2.27 0x22—PLL Modes Register (pll_modes)663.2.28 0x23—Test Register (reserved10)673.2.29 0x24, 0x25—Timing Recovery PLL Phase Offs...673.2.30 0x26, 0x27—Receiver DC Offset Register (d...673.2.31 0x28—Transmitter Calibration Register (tx...673.2.32 0x29—Transmitter Gain Register (tx_gain)683.2.33 0x2A, 0x2B—Noise-Level Histogram Threshol...693.2.34 0x2C, 0x2D—Error Predictor Pause Threshol...693.2.35 0x2E—Scrambler Synchronization Threshold ...693.2.36 0x30, 0x31—Far-End High Alarm Threshold R...693.2.37 0x32, 0x33—Far-End Low Alarm Threshold Re...693.2.38 0x34, 0x35—SNR Alarm Threshold Register (...703.2.39 0x36, 0x37—Cursor Level Register (cursor_...703.2.40 0x38, 0x39—DAGC Target Register (dagc_tar...703.2.41 0x3A—Symbol Detector Modes Register (dete...713.2.42 0x3B—Peak Detector Delay Register (peak_d...723.2.43 0x3C—Digital AGC Modes Register (dagc_mod...723.2.44 0x3D—Feed Forward Equalizer Modes Registe...733.2.45 0x3E—Error Predictor Modes Register (ep_m...733.2.46 0x40, 0x41—Phase Detector Meter Register ...743.2.47 0x42—Overflow Meter Register (overflow_me...743.2.48 0x44, 0x45—DC Level Meter Register (dc_me...743.2.49 0x46, 0x47—Signal Level Meter Register (s...753.2.50 0x48, 0x49—Far-End Level Meter Register (...753.2.51 0x4A, 0x4B—Noise Level Histogram Meter Re...753.2.52 0x4C, 0x4D—Bit Error Rate Meter Register ...763.2.53 0x4E—Symbol Histogram Meter Register (sym...763.2.54 0x50, 0x51—Noise Level Meter Register (nl...763.2.55 0x5E, 0x5F— PLL Frequency Register (pll_f...773.2.56 0x70—LEC Read Tap Select Register (linear...773.2.57 0x71—LEC Write Tap Select Register (linea...773.2.58 0x72—NEC Read Tap Select Register (nonlin...773.2.59 0x73—NEC Write Tap Select Register (nonli...783.2.60 0x74—DFE Read Tap Select Register (dfe_ta...783.2.61 0x75—DFE Write Tap Select Register (dfe_t...783.2.62 0x76—Scratch Pad Read Tap Select (sp_tap_...783.2.63 0x77—Scratch Pad Write Tap Select (sp_tap...793.2.64 0x78—Equalizer Read Select Register (eq_a...793.2.65 0x79—Equalizer Write Select Register (eq_...803.2.66 0x7A—Equalizer Microcode Read Select Regi...803.2.67 0x7B—Equalizer Microcode Write Select Reg...803.2.68 0x7C–0x7F—Access Data Register (access_da...804.0 Electrical & Mechanical Specifications814.1 Absolute Maximum Ratings814.2 Recommended Operating Conditions824.3 Electrical Characteristics834.4 Clock Timing844.5 Channel Unit Interface Timing864.6 Microcomputer Interface Timing894.6.1 Test and Diagnostic Interface Timing944.6.2 Analog Specifications964.6.3 Test Conditions994.7 Timing Measurements1014.8 Mechanical Specifications102Size: 632 KBPages: 104Language: EnglishOpen manual