PC87307 Super I/O Controller, Floppy Controller

Motherboard Description

1.8 PC87307 Super I/O Controller

Control for the integrated serial ports, parallel port, floppy drive, real-time clock, and keyboard controller is incorporated into a single component, the National Semiconductor PC87307. The PC87307 is a fully Plug and Play compatible device which provides:

∙Two NS16C550-compatible UARTs with send/receive 16 byte FIFO

⎯Support for an IrDA and Consumer IR compliant Infrared interface

∙Multi-mode bi-directional parallel port

⎯Standard mode; IBM† and Centronics† compatible

⎯Enhanced Parallel Port (EPP) with BIOS/Driver support

⎯High Speed mode; Extended Capabilities Port (ECP) compatible

∙Industry standard floppy controller with 16 byte data FIFO (2.88 MB floppy support)

∙Integrated Real Time Clock with Century calendar functionality

∙Integrated 8042 compatible keyboard controller

The PC87307 is normally configured automatically by the BIOS, but configuration of these interfaces also is possible using the CMOS Setup utility that can be invoked during boot. The serial ports can be enabled as COM1, COM2, COM2 as IrDA, or disabled. The parallel port can be configured as compatible, bi-directional, EPP/ECP, or disabled. The floppy interface can be configured for 360 KB or 1.2 MB 5¼" media or for 720 KB, 1.2 MB, 1.44 MB, or 2.88 MB 3½" media.

1.8.1Floppy Controller

The PC87307 is software compatible with the DP8473 and 82077 floppy disk controllers. The floppy interface can be configured for 360 KB or 1.2 MB 5¼" media or for 720 KB, 1.2 MB,

1.44MB, or 2.88 MB 3½" media in the BIOS setup. By default, the Floppy A interface is configured for 1.44 MB and Floppy B is disabled. Configuring the floppy interface for 1.2 MB 3½" (3-mode floppy) requires the use of a driver to operate correctly.

1.8.2Keyboard and Mouse Interface

PS/2 keyboard/mouse connectors are located on the back panel side of the motherboard. The 5V lines to these connectors are protected with a PolySwitch† circuit which acts much like a self- healing fuse, re-establishing the connection after an over-current condition is removed. While this device eliminates the possibility of having to replace a fuse, care should be taken to turn off the power before installing or removing a keyboard or mouse.

The integrated 8042 microcontroller contains the AMI Megakey keyboard/mouse controller code which, besides providing traditional keyboard and mouse control functions, supports Power- On/Reset (POR) password protection. The POR password can be defined by the user in the Setup program. The keyboard controller also provides for the following “hot-key” sequences:

∙<CTRL> <ALT> <DEL>: System software reset. This sequence performs a software reset of the computer by jumping to the beginning of the BIOS code and running the POST operation.

AP440FX specifications

The Intel AP440FX is a pivotal motherboard that was released in the late 1990s, designed to support the Intel Pentium II and Pentium III processors. Known for its robust performance and versatile functionalities, the AP440FX became a popular choice among computer enthusiasts and system builders during its time.

One of the defining features of the Intel AP440FX is its support for the Intel 440FX chipset. This chipset provided improved system performance through its use of a 66 MHz front-side bus, which allowed for faster data transfer between the CPU and the memory. The motherboard was equipped with two DIMM slots capable of supporting a maximum of 512 MB of SDRAM, providing users with the flexibility to choose the amount of memory they required for their applications.

Another notable characteristic of the AP440FX motherboard is its integrated support for various peripheral interfaces. It comes equipped with multiple ISA and PCI slots, allowing users to expand their system capabilities through the addition of various cards. The presence of two USB ports, which were relatively new at the time of its release, gave users access to a wider range of peripherals and external devices.

The Intel AP440FX also features an integrated IDE controller, enabling connection for hard drives and optical drives without the need for additional controller cards. This integrated solution simplified storage management for users and contributed to the overall efficiency of the system. The motherboard also supported SCSI through optional daughter cards, catering to users who required high-speed data transfer and reliable disk storage solutions.

Moreover, the AP440FX was designed with future upgrades in mind. Its BIOS supported plug-and-play installations, allowing users to easily configure new hardware components without extensive troubleshooting. Additionally, the ATX form factor of the motherboard contributed to its compatibility with a wide range of cases and power supplies.

In terms of power management, the Intel AP440FX incorporated advanced features such as ACPI (Advanced Configuration and Power Interface), which allowed for better power efficiency and management of power states. This feature was particularly beneficial for users looking to reduce energy consumption and improve the overall longevity of their systems.

All in all, the Intel AP440FX represented a significant advancement in motherboard technology during its era. Its combination of robust performance, upgradeability, and support for new technologies made it a popular choice for users looking to build powerful and efficient computing systems.