RG82845 S L5YQ Intel, RG82845 S L5YQ Datasheet - Page 19

• Manufacturer Part Number: RG82845 S L5YQ
• Manufacturer: Intel

Specifications of RG82845 S L5YQ

• Lead Free Status / RoHS Status: Not Compliant

2
Intel
®
82845 MCH for SDR Datasheet
Note: System address and data bus signals are logically inverted signals. In other words, the actual
R
Signal Description
This chapter provides a detailed description of the MCH signals. The signal descriptions are
arranged in functional groups according to their associated interface (see Figure 1). The states of
all of the signals during reset are provided in the System Reset section.
The “#” symbol at the end of a signal name indicates that the active, or asserted state occurs when
the signal is at a low voltage level. When “#” is not present after the signal name the signal is
asserted when at the high voltage level.
The following notations are used to describe the signal type:
I
O
I/O
s/t/s
as/t/s
The signal description also includes the type of buffer used for the particular signal:
AGTL+
AGP
CMOS
Ref
values are inverted of what appears on the system bus. This must be taken into account and the
addresses and data bus signals must be inverted inside the MCH. All processor control signals
follow normal convention. A “0” indicates an active level (low voltage) if the signal is followed by
“#” symbol, and a “1” indicates an active level (high voltage) if the signal has no “#” suffix.
Input pin
Output pin
Bi-directional Input/Output pin
Sustained Three-state. This pin is driven to its inactive state prior to three-
stating.
Active Sustained Three-state. This applies to some of the hub interface signals.
This pin is weakly driven to its last driven value.
Open Drain AGTL+ interface signal. Refer to the AGTL+ I/O Specification for
complete details. The MCH integrates AGTL+ termination resistors.
AGP interface signals. These signals are compatible with AGP 2.0 1.5 V
Signaling Environment DC and AC Specifications. The buffers are not 3.3 V
tolerant.
CMOS buffers.
Voltage reference signal
Signal Description
19