Intel G540T CM8062301047004 Manuale Utente

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CM8062301047004
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Intel
®
 Celeron
®
 Processor on 0.13 Micron Process in the 478-Pin Package
 Datasheet
Electrical Specifications
2.7
Asynchronous GTL+ Signals
The Celeron processor on 0.13 micron process does not use CMOS voltage levels for any signals 
that connect to the processor. As a result, legacy input signals such as A20M#, IGNNE#, INIT#, 
LINT0/INTR, LINT1/NMI, SMI#, SLP#, and STPCLK# use GTL+ input buffers. Legacy output 
FERR# and other non-AGTL+ signals (THERMTRIP# and PROCHOT#) use GTL+ output 
buffers. All of these signals follow the same DC requirements as AGTL+ signals. However, the 
outputs are not actively driven high (during a logical 0 to 1 transition) by the processor (the major 
difference between GTL+ and AGTL+). These signals do not have setup or hold time specifications 
in relation to BCLK[1:0]. However, all of the Asynchronous GTL+ signals must be asserted for at 
least two BCLKs for the processor to recognize them. See 
 for the DC 
and AC specifications for the Asynchronous GTL+ signal groups. See 
 for additional 
timing requirements for entering and leaving the low power states.
2.8
Test Access Port (TAP) Connection
Because of the voltage levels supported by other components in the Test Access Port (TAP) logic, 
it is recommended that the Celeron processor on 0.13 micron process be first in the TAP chain and 
be followed by any other components within the system. A translation buffer should be used to 
connect to the rest of the chain unless one of the other components is capable of accepting an input 
of the appropriate voltage level. Similar considerations must be made for TCK, TMS, and TRST#. 
Two copies of each signal may be required, with each driving a different voltage level.
2.9
System Bus Frequency Select Signals (BSEL[1:0]) 
The BSEL[1:0] are output signals that are used to select the frequency of the processor input clock 
(BCLK[1:0]). 
 defines the possible combinations of the signals, and the frequency 
associated with each combination. The required frequency is determined by the processor, chipset, 
and clock synthesizer. All agents must operate at the same frequency. 
The Celeron processor on 0.13 micron process currently operates at a 400 MHz system bus 
frequency (selected by a 100 MHz BCLK[1:0] frequency). Individual processors will operate only 
at their specified system bus frequency.
For more information about these pins, refer to 
 and the appropriate Platform Design 
Guide.
Table 5.  BSEL[1:0] Frequency Table for BCLK[1:0]
BSEL1
BSEL0
Function
L
L
100 MHz
L
H
RESERVED
H
L
RESERVED
H
H
RESERVED