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Anleitung Zusammenfassung
The controllerless-based solutions include the 536EP for PCI and Mini-PCI. Refer to the chipset datasheets for the detailed chipset descriptions (public order numbers 273503-001, 273xxx-001, 273xxx-001, 273xxx-001, and 273xxx-001). The controllerless-based chipset, as the name implies, does not have a dedicated hardware controller. The controller functions are executed by the CPU. This developer’s manual includes the AT command sets for data, fax, and voice and the UART interface and emulation. Like the earlier solutions from Intel, the 536EX chipsets support a variety of applications without the need of additional firmware development. Note, the supported AT commands are firmware or driver version dependent. 1.1 Controllerless Modem Driver Overview 1.1.1 Windows* Millennium Edition (Windows Me), Windows 2000, Windows XP, and Windows NT* 4 The controllerless modem chipsets are integrated into the Microsoft* Windows* Me, Windows 2000, Windows XP, and Windows NT* 4 operating systems via proprietary Intel® Windows Driver Model (WDM) modem drivers. These drivers are fully plug and play capable and conform to all Microsoft WHQL certification requirements. The functional block diagram in Figure 1 shows the common WDM architecture for the Microsoft’s operating systems supporting common WDM drivers model. User-mode application, via special Windows API (FILE, TAPI, UNIMODEM), can access a virtual COM port provided by the Intel WDM driver. The data flow is converted inside the driver in accordance with some compression and a channel level protocol and passed to the DSP. The control flow follows the common Microsoft WDM driver model. The Intel WDM driver is installed as a stack of filter drivers below the system modem.sys driver. 536EX Chipset Developer’s Manual Intel Confidential Introduction Figure 1. WDM Driver Block Diagram WDM driver Intels51.sys Kernel - ring0 Modem drivers stack Hardware PCI bus User applications User applications virtual COM port, channel protocols layer 1.1.2 Windows 95 and Windows 98 When the controllerless modem chipsets are used with Microsoft Windows 95 and Windows 98 applications, the traditional UART and serial port emulations are replaced by the proprietary HaM Mini Port driver (see Figure 2). Instead of transferring commands to UART virtual registers, then to a serial port, the HaM Port Driver sends commands directly to the Windows virtual machine driver VCOMM.VxD. This low-level communication driver supports the Win16 and Win32 Communication APIs. Like the WDM drivers, the Mini Port VxD drivers are fully plug and play and conform to Microsoft WHQL certification requirements. 536EX Chipset Developer’s Manual Intel Confidential Introduction When the controllerless chipsets are used with MS-DOS* applications, however, a UART emulation is required. Intel provides an additional driver called Intelsdb.VxD, which includes a UART emulation. Please refer to Section 9.1, “UART Emulation in the Controllerless Modem” on page 92 for an explanation of the 536EX UART emulation. The Intelsdb.VxD driver interacts directly with the VCOMM.VxD driver using the Win16 and Win32 Communication APIs. Figure 2. VxD Mini Port Driver Block Diagram MS-DOS. APPLICATION WINDOWS. APPLICATION TAPI Win 16 Unimodem COMM.DRV VCOMM.VXD HaM Port Driver Interrupt Services Chipset Hardware Intelsdb.VXD SYSTEM VIRTUAL MACHINE NON-SYSTEM VIRTUAL MACHINE MS-DOS SHELL APPLICATION OR DRIVER 1.2 V.90/V.92 and V.34 Data Modes The 536EX chipset defaults to the V.90 or V.92 mode depending on the driver version. The V.90/ V.92 mode allows receive data rates of up to 56,000 kbps over the PSTN (public switched telephone network) only in connections with equipment-compatible ISPs (Internet Service Providers); however, FCC regulations limit receive speeds to 53,333 kbps due to excessive power demands at higher speeds. In modem-to-modem connections, V.90/V.92 mode falls back to V.34 mode in both the transmit and receive directions. The chipsets implement all data rates and modulation schemes for ITU-T (International Telecommunications Union-Telecommunications) standards V.34, V.32 bis, V.32, V.22 bis, V.22, V.21, Bell 212A, and Bell 103. 536EX Chipset Developer’s Manual Intel Confidential Introduction 1.3 Modem Connection Overview The DCE (modem) operates in one of two states: command or online. In each state, both data and commands (including DCE responses) are transferred through the UART THR (Transmit Holding register) and the RBR (Receiver Buffer register). The modem defaults to the command state. In the command state, the DTE (host) communicates to the modem through AT commands and S-registers. AT commands are character strings that help guide modem operation. S-registers are internal modem registers that the DTE can access. The S- registers contain modem status and configuration information. Many of the AT commands indirectly affect the contents of the S-registers. The AT command set and S-registers are divided into the following m...