CX81801-94 Conexant Systems, Inc., CX81801-94 Datasheet
CX81801-94
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CX81801-94 Summary of contents
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... CX81801-9x SmartV.XX Modem V.92/V.34/V.32bis Modem in 28-Pin or 38-Pin CTLGA with CX20493 SmartDAA Data Sheet Doc. No. 102179D November 21, 2003 ...
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... CX81801-9x SmartV.XX Modem Data Sheet Revision Record Revision © 2003 Conexant Systems, Inc. All Rights Reserved. Information in this document is provided in connection with Conexant Systems, Inc. (“Conexant”) products. These materials are provided by Conexant as a service to its customers and may be used for informational purposes only. Conexant assumes no responsibility for errors or omissions in these materials ...
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... CX81801-9x SmartV.XX Modem Data Sheet Contents 1. Introduction..........................................................................................................................................1-1 1.1 Overview ......................................................................................................................................................................... 1-1 1.2 Features .......................................................................................................................................................................... 1-4 1.2.1 General Modem Features................................................................................................................................ 1-4 1.2.2 SmartDAA Features ........................................................................................................................................ 1-5 1.2.3 Applications.................................................................................................................................................... 1-6 1.3 Technical Overview......................................................................................................................................................... 1-6 1.3.1 General Description ........................................................................................................................................ 1-6 1.3.2 Embedded MCU Firmware.............................................................................................................................. 1-6 1.3.3 Operating Modes ............................................................................................................................................ 1-6 1.3.3.1 Data/Fax Modes.......................................................................................................................... 1-6 1.3.3.2 V.44 Data Compression.............................................................................................................. 1-7 1.3.3.3 Synchronous Access Mode (SAM) - Video Conferencing.......................................................... 1-7 1.3.3.4 TAM Mode.................................................................................................................................. 1-7 1.3.3.5 Worldwide Operation.................................................................................................................. 1-8 1.3.4 Reference Designs.......................................................................................................................................... 1-9 1.4 Hardware Description ..................................................................................................................................................... 1-9 1 ...
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... CX81801 Modem Hardware Pins and Signals ................................................................................................................ 3-1 3.1.1 CX81801 Modem 28-Pin CTLGA with Serial Interface Signal Summary........................................................ 3-1 3.1.1.1 LSD Interface (Through DIB)...................................................................................................... 3-1 3.1.1.2 Call Progress Speaker Interface ................................................................................................. 3-1 3.1.1.3 Serial DTE Interface and Indicator Outputs ................................................................................ 3-1 3.1.2 CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Assignments and Signal Definitions ................... 3-2 iv Conexant 102179D ...
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... LSD Interface (Through DIB)...................................................................................................... 3-6 3.1.3.2 Call Progress Speaker Interface ................................................................................................. 3-6 3.1.3.3 Serial EEPROM Interface............................................................................................................ 3-6 3.1.3.4 Parallel Host Bus Interface ......................................................................................................... 3-6 3.1.4 CX81801 Modem 38-Pin CTLGA with Parallel Interface Pin Assignments and Signal Definitions................. 3-7 3.1.5 Electrical Characteristics .............................................................................................................................. 3-11 3.2 CX20493 LSD Hardware Pins and Signals ................................................................................................................... 3-12 3.2.1 CX20493 LSD Signal Summary.................................................................................................................... 3-12 3.2.1.1 CX81801 Interface (Through DIB)............................................................................................ 3-12 3 ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figures Figure 1-1. SmartV.XX Modem Simplified Interface Diagram ............................................................................................ 1-3 Figure 3-1. CX81801 Modem 28-Pin CTLGA with Serial Interface Hardware Signals ........................................................ 3-2 Figure 3-2. CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Signals .................................................................. 3-3 Figure 3-3. CX81801 Modem 38-Pin CTLGA with Parallel Interface Hardware Signals...................................................... 3-7 Figure 3-4 ...
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... Table 2-1. +MS Command Automode Connectivity ............................................................................................................ 2-3 Table 3-1. CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Signals.................................................................... 3-3 Table 3-2. CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Signal Definitions ................................................... 3-4 Table 3-3. CX81801 Modem 38-Pin CTLGA with Parallel Interface Pin Signals ................................................................. 3-8 Table 3-4. CX81801 Modem 38-Pin CTLGA with Parallel Interface Hardware Signal Definitions....................................... 3-9 Table 3-5 ...
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... CX81801-9x SmartV.XX Modem Data Sheet viii This page is intentionally blank. Conexant 102179D ...
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... DAA features, the SmartDAA architecture simplifies application design, minimizes layout area, and reduces component cost. The SmartV.XX Modem device set, consisting of a CX81801 Modem in a 28-pin (serial interface) or 38-pin (parallel interface) CTLGA and a CX20493 SmartDAA LSD in a 28- pin QFN, supports data/fax/TAM operation with hardware-based modem controller, digital signal processing, and DAA/telephone line interface functions (Figure 1-1) ...
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... V.92 Data, QC, Modem (LSD) MOH, PCM [28-Pin CTLGA] [28-Pin QFN] Part No. Part No. CX81801-94 CX20493-21 CX81801-92 CX20493-21 CX81801-93 CX20493-21 Lead-Free Device Sets* CX81801-94 CX20493-31 CX81801-92 CX20493-31 CX81801-93 CX20493-31 SmartV.XX Line Side Device V.92 Data, QC, Modem (LSD) MOH, PCM [38-Pin CTLGA] [28-Pin QFN] Part No. ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 1-1. SmartV.XX Modem Simplified Interface Diagram 28.224 MHz Clock Source CX81801 Modem 28-Pin or 38-Pin CTLGA SmartDAA Interface Serial or Parallel* Microcontroller Interface Unit (MCU) Modem Data Pump (MDP) RAM (32K x 8) (256K x 8) *Parallel interface supported only in 38-pin version. ...
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... CX81801-9x SmartV.XX Modem Data Sheet 1.2 Features 1.2.1 General Modem Features • Data modem − − − • Data compression and error correction − − − • Fax modem send and receive rates up to 14.4 kbps − − • V.80 synchronous access mode supports host-controlled communication protocols with H.324 interface support • ...
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... Remote hang-up detection for efficient call termination • Extension pickup detection • Call waiting detection • Digital PBX line protection • Meets worldwide DC V-I masks requirements 102179D CX81801 Modem in 28-pin or 38-pin CTLGA CX20493 LSD in 28-pin QFN 205 mW (Normal Mode (Sleep Mode) Conexant 1-5 ...
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... CX81801-9x SmartV.XX Modem Data Sheet 1.2.3 Applications • Embedded systems • Set-top boxes • Handheld computers • Gaming devices • Point of sale terminals • Remove monitoring and data collection systems • Modem modules 1.3 Technical Overview 1.3.1 General Description Modem operation, including dialing, call progress, telephone line interface, telephone handset interface, and host DTE interface functions are supported and controlled through the V ...
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... CX81801-9x SmartV.XX Modem Data Sheet conversation. The data connection resumes upon incoming call termination. The server must support Modem-on-Hold functionality. • PCM upstream, which boosts the upstream data rates between the user and V.92 server. A maximum of 48 kbps upstream rate is supported when connected to a V.92 server that supports PCM upstream ...
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... CX81801-9x SmartV.XX Modem Data Sheet 1.3.3.5 Worldwide Operation The modem operates in TBR21-compliant and other countries. Country-dependent modem parameters for functions such as dialing, carrier transmit level, calling tone, call progress tone detection, answer tone detection, blacklisting, caller ID, and relay control are programmable. SmartDAA technology allows a single PCB design and single BOM to be homologated worldwide ...
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... The DIB transformer couples power and clock from the CX81801 to the LSD. The DIB data channel supports bidirectional half-duplex serial transfer of data, control, and status information between the CX81801 and the LSD over two lines. ...
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... The CLK input is also accepted from the DIB transformer secondary winding through a capacitor and a resistor in series. Information is transferred between the LSD and the CX81801 through the DIB_P and DIB_N pins. These pins connect to the CX81801 DIB_DATAP and DIB_DATAN pins, respectively, through the DIB. ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2. Technical Specifications 2.1 Serial DTE Interface Operation 2.1.1 Automatic Speed/Format Sensing Command Mode and Data Modem Mode. The modem can automatically determine the speed and format of the data sent from the DTE. The modem can sense speeds of 300, ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.2 Parallel Host Bus Interface Operation Command Mode and Data Modem Mode. The modem can operate at rates up to 230.4 kbps by programming the Divisor Latch in the parallel interface registers. Fax Modem Mode. In V.17 mode, the modem can operate at rates up to 230.4 kbps by programming the Divisor Latch in the parallel interface registers ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.3.7 Connection Speeds The modem functions as a data modem when the +FCLASS=0 command is active. Line connection can be selected using the +MS command. The +MS command selects modulation, enables/disables automode, and selects minimum and maximum line speeds (Table 2-1). Table 2-1. +MS Command Automode Connectivity ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.4.3 Escape Sequence Detection The +++ escape sequence can be used to return control to the command mode from the data mode. Escape sequence detection is disabled Register value greater than 127. 2.4.4 BREAK Detection The modem can detect a BREAK signal from either the DTE or the remote modem. The \Kn command determines the modem response to a received BREAK signal ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.5 V.92 Features Modem-on-Hold, quick connect, and PCM upstream are only available when connecting in V.92 data mode. V.92 features are only available when the server called is a V.92 server that supports that particular feature. 2.5.1 Modem-on-Hold The Modem-on-Hold (MOH) function (V.92 models only) enables the modem to place an Internet data connection on hold while using the same line to accept an incoming or place an outgoing voice call ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.6.3 V.44 Data Compression V.44 data compression encodes pages and files associated with Web pages more efficiently than V.42 bis. These files include WEB pages, graphics and image files, and document files. V.44 can provide an effective data throughput rate up to DTE rate for a 56-kbps connection ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.7 Telephony Extensions The following telephony extension features are supported and are typically implemented in designs for set-top box applications and TAM software applications to enhance end- user experience: • Line In Use detection • Extension Pickup detection • Remote Hang-up detection The telephony extension features are enabled through the -STE command ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.8 Fax Class 1 and Fax Class 1.0 Operation Facsimile functions operate in response to fax class 1 commands when +FCLASS fax class 1.0 commands when +FCLASS=1.0. In the fax mode, the on-line behavior of the modem is different from the data (non-fax) mode. After dialing, modem operation is controlled by fax commands. Some AT commands are still valid but may operate differently than in data modem mode ...
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... CX81801-9x SmartV.XX Modem Data Sheet 2.10.3 Voice Transmit Mode This mode is entered when the +VTX command is active in order to playback voice or audio data to the TXA output, typically to a speaker/handset or to the telephone line. Digitized voice data is decompressed and converted to analog form at the original compression quantization sample-per-bits rate then output to the TXA output ...
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... CX81801-9x SmartV.XX Modem Data Sheet • Carrier transmit level (through S91 for data and S92 for fax). The maximum, minimum, and default values can be defined to match specific country and DAA requirements. • Calling tone is generated in accordance with V.25. Calling tone may be toggled (enabled/disabled) by inclusion of a “ ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3. Hardware Interface 3.1 CX81801 Modem Hardware Pins and Signals 3.1.1 CX81801 Modem 28-Pin CTLGA with Serial Interface Signal Summary 3.1.1.1 LSD Interface (Through DIB) The DIB interface signals are: • Clock and Power Positive (PWRCLKP); output • Clock and Power Negative (PWRCLKN); output • ...
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... CX81801 Modem 28-pin CTLGA hardware interface signals are shown by major interface in Figure 3-1, are shown by pin number in Figure 3-2, and are listed by pin number in Table 1-1. CX81801 Modem hardware interface signals are defined in Table 3-2. Figure 3-1. CX81801 Modem 28-Pin CTLGA with Serial Interface Hardware Signals CRYSTAL CIRCUIT SOURCE ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 3-2. CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Signals Table 3-1. CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Signals Pin No 102179D CX81801 28-Pin CTLGA Top View Signal Name Pin No ...
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... Data Positive. Transfers data, control, and status information between the CX81801 and the LSD. Connect to LSD through DIB data positive channel components. Idd/Odd Data Negative. Transfers data, control, and status information between the CX81801 and the LSD. Connect to LSD through DIB data negative channel components. Conexant 102179D ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 3-2. CX81801 Modem 28-Pin CTLGA with Serial Interface Pin Signal Definitions (Continued) Label Pin I/O TXD RXD CTS RLSD RI DTR RTS RESERVED 14 RESERVED 6, 8 Note: I/O Types: See Table 3-5. 102179D I/O Type Signal Name/Description V ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.1.3 CX81801 Modem 38-Pin CTLGA with Parallel Interface Signal Summary 3.1.3.1 LSD Interface (Through DIB) The DIB interface signals are: • Clock and Power Positive (PWRCLKP); output • Clock and Power Negative (PWRCLKN); output • Data Positive (DIB_DATAP); input/output • ...
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... CX81801 Modem 38-pin CTLGA hardware interface signals are shown by major interface in Figure 3-3 are shown by pin number in Figure 3-4, and are listed by pin number in Table 3-3. CX81801 Modem hardware interface signals are defined in Table 3-4. Figure 3-3. CX81801 Modem 38-Pin CTLGA with Parallel Interface Hardware Signals CRYSTAL CIRCUIT SOURCE ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 3-4. CX81801 Modem 38-Pin CTLGA with Parallel Interface Pin Signals Table 3-3. CX81801 Modem 38-Pin CTLGA with Parallel Interface Pin Signals Pin No 3-8 CX81801 38-Pin CTLGA Top View Signal Name Pin No ...
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... CX81801 and the LSD. Connect to LSD through DIB data positive channel components. Idd/Odd Data Negative. Transfers data, control, and status information between the CX81801 and the LSD. Connect to LSD through DIB data negative channel components. NVRAM Interface It/Ot2 NVRAM Clock. During normal operation, NVMCLK output high enables the EEPROM ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 3-4. CX81801 Modem 38-Pin CTLGA with Parallel Interface Hardware Signal Definitions (Continued) Label Pin I/O HCS HWT HRD HINT 19 O HA0-HA2 6-8 I HD0-HD7 12, 15-17, I/O 22, 23, 27, 28 RESERVED 24 RESERVED Note: I/O Types: See Table 3-5. 3-10 I/O Type Signal Name/Description ...
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... VCC Power GND Ground NOTES: 1. See DC characteristics in Table 3-6. 2. I/O Type corresponds to the device Pad Type. The I/O column in signal interface tables refers to signal I/O direction used in the application. Table 3-6. CX81801 Modem DC Electrical Characteristics Parameter Symbol Input Voltage Low VIL Input Voltage High VIH Input Hysteresis VH ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.2 CX20493 LSD Hardware Pins and Signals 3.2.1 CX20493 LSD Signal Summary 3.2.1.1 CX81801 Interface (Through DIB) The DIB interface, power, and ground signals are: • Clock (CLK, pin 26); input • Digital Power (PWR+, pin 7); unregulated input power • ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.2.1.4 General Purpose Input/Output There is one unassigned general purpose input/output pin: • General Purpose Input/Output 1 (GPIO1, pin 1); input/output 3.2.1.5 No Connects Three pins are not used: • No Connect 1 (NC1, pin 8); no internal connection • No Connect 2 (NC2, pin 22); no internal connection • ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 3-6. CX20493 LSD 28-Pin QFN Pin Signals Table 3-7. CX20493 LSD 28-Pin QFN Pin Signals Pin 3-14 CX20493 Signal Label GPIO1 15 AVdd VRef 18 RBias 19 AGnd 20 PWR+ 21 NC1 22 RXI EIC ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 3-8. CX20493 LSD Hardware Signal Definitions Label Pin I/O AVdd 2 PWR AGnd 6 AGND_LSD VRef 4 REF Vc 3 REF PWR+ 7 PWR DVdd 24 PWR DGnd 23 DGND_LSD PADDLE — AGND_LSD CLK 26 I DIB_P 27 I/O DIB_N 28 I/O 102179D I/O Type Signal Name/Description System Signals PWR Regulated Power Output ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 3-8. CX20493 LSD Hardware Signal Definitions (Continued) Label Pin I/O RAC1 21 I TAC1 20 I RAC2 19 I TAC2 18 I EIC 11 O TRDC 12 I EIO 17 O DC_GND 15 GND EIF 16 I RXI 9 I RBias TXO 14 O TXF 13 I GPIO1 ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 3-9. CX20493 LSD GPIO DC Electrical Characteristics Parameter Input Voltage Input Voltage Low Input Voltage High Output Voltage Low Output Voltage High Input Leakage Current Output Leakage Current (High Impedance) GPIO Output Sink Current at 0.33 V maximum GPIO Output Source Current at 2.97 V minimum GPIO Rise Time/Fall Time Test Conditions unless otherwise stated: DVdd = +3.3V +5% ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.3 Electrical and Environmental Specifications 3.3.1 Operating Conditions, Absolute Maximum Ratings, and Power Requirements The operating conditions are specified in Table 3-11. The absolute maximum ratings are listed in Table 3-12. The current and power requirements are listed in Table 3-13. Table 3-11. Operating Conditions ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 3-13. Current and Power Requirements Mode Normal Mode: Off-hook, normal data connection Normal Mode: On-hook, idle, waiting for ring Sleep Mode Notes: 1. Operating voltage: VDD = +3.3V ± 0.3V. 2. Test conditions: VDD = +3.3V for typical values; VDD = +3.6V for maximum values. ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.3.2 Interface and Timing Waveforms 3.3.2.1 Serial DTE Interface The serial DTE interface waveforms for 4800 and 9600 bps are illustrated in Figure 3-7. Figure 3-7. Waveforms - Serial DTE Interface TXCLK 4800 BPS TXD 4800 BPS TXCLK 9600 BPS TXD 9600 BPS NOTE: THIS FIGURE IS VALID FOR SYNCHRONOUS MODE ONLY ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.3.2.2 Parallel Host Bus Timing The parallel host bus timing is listed in Table 3-14 and illustrated in Figure 3-8. Table 3-14. Timing - Parallel Host Bus Symbol Parameter t Address Setup AS t Address Hold AH t Chip Select Setup CS t Chip Select Hold CH t HRD# Strobe Width ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 3-8. Waveforms - Parallel Host Bus HA[2-0] HCS# HRD# HWT# HD[7-0] HA[2-0] HCS# HRD# HWT# HD[7-0] 3- DRH a. Host Read DWH Host Write Conexant 100491 F3-10 WF-HB 102179D ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3.4 Crystal Specifications Crystal specifications are listed in Table 3-15. Table 3-15. Crystal Specifications Frequency Calibration Tolerance Frequency Stability vs. Temperature Frequency Stability vs. Aging Oscillation Mode Calibration Mode Load Capacitance, C Shunt Capacitance, C Series Resistance, R Drive Level Operating Temperature Storage Temperature 102179D Characteristic 28 ...
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... CX81801-9x SmartV.XX Modem Data Sheet 3-24 This page is intentionally blank. Conexant 102179D ...
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... CX81801-9x SmartV.XX Modem Data Sheet 4. Package Dimensions The 28-pin CTLGA package dimensions are shown in Figure 4-1. The 38-pin CTLGA package dimensions are shown in Figure 4-2. The 28-pin QFN package dimensions are shown in Figure 4-3. 102179D Conexant 4-1 ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 4-1. Package Dimensions - 28-Pin CTLGA Pin 1 Identifier D TOP VIEW Solder Mask DETAIL A (Rotated 90 Deg.) Pin FOOTNOTE: (1) Test Pins are exposed on the bottom of the device. Do not place any exposed traces, vias, test points, or pads in this area. 4-2 See Detail A ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 4-2. Package Dimensions - 38-Pin CTLGA Pin 1 Identifier D TOP VIEW Solder Mask DETAIL A (Rotated 90 Deg.) Pin FOOTNOTE: (1) Test Pins are exposed on the bottom of the device. Do not place any exposed traces, vias, test points, or pads in this area. 102179D ...
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... CX81801-9x SmartV.XX Modem Data Sheet Figure 4-3. Package Dimensions - 28-Pin QFN Pin 1 Identifier 2 3 TOP VIEW TERMINAL TIP NOTES: 1. DIMENSION b APPLIES TO PLATED TERMINAL AND IS MEASURED BETWEEN 0.20 AND 0.25mm FROM TERMINAL TIP. 2. PACKAGE WARPAGE MAX 0.05mm. 3. APPLIED FOR EXPOSED PAD AND TERMINALS. EXCLUDE EMBEDDING PART OF EXPOSED PAD FROM MEASURING ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5. Parallel Host Interface The modem supports a 16550A interface in parallel interface versions. The 16550A interface can operate in FIFO mode or non-FIFO mode. Non-FIFO mode is the same as 16450 interface operation. FIFO mode unique operations are identified. 5.1 Overview The parallel interface registers and the corresponding bit assignments are shown in Table 5-1 ...
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... CX81801-9x SmartV.XX Modem Data Sheet Table 5-1. Parallel Interface Registers Register Register No. Name 7 Scratch Register (SCR) 6 Modem Status Register (MSR) Data Carrier 5 Line Status Register (LSR) RX FIFO 4 Modem Control Register (MCR) 3 Line Control Register (LCR) Divisor Latch Access Bit 2 Interrupt Identify Register (IIR) ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2 Register Signal Definitions 5.2.1 IER - Interrupt Enable Register (Addr = 1, DLAB = 0) The IER enables five types of interrupts that can separately assert the HINT output signal (Table 5-2). A selected interrupt can be enabled by setting the corresponding enable bit disabled by setting the corresponding enable bit Disabling an interrupt in the IER prohibits setting the corresponding indication in the IIR and assertion of HINT ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2.2 FCR - FIFO Control Register (Addr = 2, Write Only) The FCR is a write-only register used to enable FIFO mode, clear the RX FIFO and TX FIFO, enable DMA mode, and set the RX FIFO trigger level. Bits 7-6 FCR7 and FCR6 set the trigger level for the RX FIFO (Receiver Data Available) interrupt ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2.3 IIR - Interrupt Identifier Register (Addr = 2) The Interrupt Identifier Register (IIR) identifies the existence and type five prioritized pending interrupts. Four priority levels are set to assist interrupt processing in the host. The four levels, in order of decreasing priority, are: Highest: Receiver Line Status, 2: Receiver Data Available or Receiver Character Timeout Buffer Empty, and 4: Modem Status ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2.4 LCR - Line Control Register (Addr = 3) The Line Control Register (LCR) specifies the format of the asynchronous data communications exchange. Bit 7 This bit must be set access the Divisor latch registers during a read or write operation. It must be reset access the Receiver Buffer, the Transmitter Buffer, or the Interrupt Enable Register ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2.5 MCR - Modem Control Register (Addr = 4) The Modem Control Register (MCR) controls the interface with the modem or data set. Bit 7-5 Always 0. Bit 4 When this bit is set the diagnostic mode is selected and the following occurs: Data written to the Transmit Buffer is looped back to the Receiver Buffer. ...
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... CX81801-9x SmartV.XX Modem Data Sheet Bit 5 This bit, when set, indicates that the TX Buffer is empty and the modem can accept a new character for transmission. In addition, this bit causes the modem to issue an interrupt to the host when the Transmit Holding Register Empty Interrupt Enable bit (IIR1) is set to 1 ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2.7 MSR - Modem Status Register (Addr = 6) The Modem Status Register (MSR) reports current state and change information of the modem. Bits 4-7 supply current state and bits 0-3 supply change information. The change bits are set whenever a control input from the modem changes state from the last MSR read by the host ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.2.10 Divisor Registers (Addr = 0 and 1, DLAB = 1) The Divisor Latch LS (least significant byte) and Divisor Latch MS (most significant byte) are two read-write registers at locations 0 and 1 when DLAB = 1, respectively. The baud rate is selected by loading each divisor latch with the appropriate hex value. ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5.3.2 Receiver Character Timeout Interrupts When the FIFO mode is enabled (FCR0 = 1) and receiver interrupt (Receiver Data Available) is enabled (IER0 = 1), receiver character timeout interrupt operation is as follows Receiver character timeout interrupt code (IIR0-IIR3 = Ch) is set if at least one ...
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... CX81801-9x SmartV.XX Modem Data Sheet 5-12 This page is intentionally blank. Conexant 102179D ...
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NOTES ...
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General Information: U.S. and Canada: (800) 854-8099 International: (949) 483-6996 Headquarters – Newport Beach 4000 MacArthur Blvd. Newport Beach, CA 92660 ...