IEI Technology WAFER-8523, User Manual

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WAFER-8523 User Manual
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2.6.4 Intel
®
ICH4 PCI Interface
The ICH4 PCI interface provides a 33 MHz, Rev. 2.2 compliant implementation. All PCI
signals are 5 V tolerant, except PME#. The ICH4 integrates a PCI arbiter that supports up
to six external PCI bus masters in addition to the internal ICH4 requests.
2.6.5 Intel
®
ICH4 Real Time Clock
256 bytes of battery backed RAM is provided by the Motorola MC146818A real time clock
(RTC) integrated into the ICH4. The RTC operates on a 3V battery and 32.768 KHz crystal.
The RTC keeps track of the time and stores system data even when the system is turned
off.
2.6.6 Intel
®
ICH4 USB Controller
Up to six high-speed, full-speed or low-speed USB devices are supported by the ICH4.
High-speed USB 2.0, with data transfers of up to 480Mb/s, is enabled with the ICH4
integrated Enhanced Host Controller Interface (EHCI) compliant host controller. USB
full-speed and low-speed signaling is supported by the four ICH4 integrated Universal
Host Controller Interface (UHCI) controller.
2.6.7 PCI-to-ISA Bridge
A PC/104 expansion connector on the WAFER-8523 facilitates ISA bus expansion. The
PC/104 connector is interfaced to the CPU, through an ITE IT8888G PCI to ISA bridge
single function device. The ITE IT8888G is a bridge between the PCI bus and the ISA bus.
The 32-bit PCI bus interface on the IT8888G is compliant with PCI Specification v2.1 and
supports both PCI Bus Master and Slave.