82845MP Datasheet, PDF (20/157 Pages) Intel Corporation – Intel 845 Family Chipset-Mobile 82845MP/82845MZ Chipset Memory Controller Hub Mobile (MCH-M)

Intel^®82845MP/82845MZ Chipset-Mobile (MCH-M)
R
2. Signal Description
This section provides a detailed description of Intel 845MP/845MZ Chipset MCH-M signals. The signals
are arranged in functional groups according to their associated interface. 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
Input pin
O
Output pin
I/O
Bi-directional Input/Output pin
s/t/s
Sustained Tristate. This pin is driven to its inactive state prior to tri-stating.
as/t/s
Active Sustained Tristate. This applies to some of the hub interface signals. This pin
is weakly driven to its last driven value.
The signal description also includes the type of buffer used for the particular signal:
AGTL+
Open Drain AGTL+ interface signal. Refer to the AGTL+ I/O Specification for
complete details. The Intel^®845MP/845MZ Chipset MCH-M integrates AGTL+
termination resistors.
AGP
AGP interface signals. These signals are compatible with AGP 2.0 1.5v Signaling
Environment DC and AC Specifications. The buffers are not 3.3v tolerant.
CMOS
CMOS buffers.
Ref
Voltage reference signal.
Note:
System address and data bus signals are logically inverted signals. The actual 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 Intel 845MP/845MZ Chipset MCH-M. 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.
20
Datasheet
250687-002