PC87417

The National Semiconductor® PC8741x family of LPC ServerI/ O devices ("PC8741x") comprises highly integrated Advanced I/O products. The PC8741x is targeted for a wide range of servers and workstations that use the Low Pin Count (LPC) bus for the host interface and the serial ACCESS.bus or SMBus® for the embedded controller interface. The PC8741x features an X-Bus extension for read and write operations over the X-Bus for both LPC and ACCESS.bus cycles. Boot Flash and I/O devices can be accessed over this X-Bus.

Embedded controllers can access the PC8741x and its X-Bus via the ACCESS.bus or SMBus serial interface when VSB exists, regardless of the LPC bus state. Some of the PC8741x logical devices can be disabled, or their pins can be floated, under control of the VSB-powered serial bus. The PC8741x provides a VSB-powered high-frequency clock for on-chip peripherals and for other VSB-powered platform components.

The PC8741x's extended wake-up support complements the chipset's ACPI controller and the platform embedded controllers. The PC8741x can monitor the Power and Sleep buttons and control the power supply of simple platforms that lack an embedded controller. The System Wake-Up Control (SWC) module is powered by VSB and VBAT power supplies. It supports flexible wake-up and power-off request mechanisms in any sleep state. It features Main and Standby power-on elapsed-time counters.

The PC8741x also incorporates a Floppy Disk Controller (FDC), two serial ports (UARTs), a Keyboard and Mouse Controller (KBC), a Real-Time Clock (RTC), a fully compliant IEEE 1284 Parallel Port, General-Purpose Input/Output (GPIO) for a total of 51 ports and an Interrupt Serializer for Parallel IRQs.