Intel 537EX manual Introduction, 1.1Controllerless Modem Driver Overview, Intel Confidential

Introduction 1

This developer’s manual describes the software interface for Intel® 536EX (controllerless and controller) chipset solutions. 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.

1.1Controllerless Modem Driver Overview

1.1.1Windows* 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 7

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