22
Datasheet
Electrical Specifications
.
2.7
GTL+ Asynchronous Signals
Legacy input signals such as A20M#, IGNNE#, INIT#, SMI#, and STPCLK# use CMOS input
buffers. All of these signals follow the same DC requirements as GTL+ signals; however, the
outputs are not actively driven high (during a logical 0 to 1 transition) by the processor. These
signals do not have setup or hold time specifications in relation to BCLK[1:0].
All of the GTL+ Asynchronous signals are required to be asserted/de-asserted for at least six
BCLKs for the processor to recognize the proper signal state. See
Section 2.11 for the DC
specifications for the GTL+ Asynchronous signal groups. See
Section 6.2 for additional timing
requirements for entering and leaving the low power states.
Table 2-4. Signal Characteristics
Signals with RTT
Signals with no RTT
A[35:3]#, ADS#, ADSTB[1:0]#, AP[1:0]#, BINIT#,
BNR#, BOOTSELECT1, BPRI#, D[63:0]#, DBI[3:0]#,
DBSY#, DEFER#, DP[3:0]#, DRDY#, DSTBN[3:0]#,
DSTBP[3:0]#, HIT#, HITM#, LOCK#, MCERR#,
PROCHOT#, REQ[4:0]#, RS[2:0]#, RSP#, TRDY#,
NOTES:
1.
The BOOTSELECT signal has a 500–5000
Ω pull-up to V
TT rather than on-die termination.
2.
EDRDY# and PC_REQ# are not features of the Celeron D processor in the 775-land package. They are included here for
future processor compatibility.
A20M#, BCLK[1:0], BPM[5:0]#, BR0#, BSEL[2:0],
COMP[5:0], FERR#/PBE#, IERR#, IGNNE#,
INIT#, LINT0/INTR, LINT1/NMI, PWRGOOD,
RESET#, SKTOCC#, SMI#, STPCLK#, TDO,
TESTHI[13:0], THERMDA, THERMDC,
THERMTRIP#, VID[5:0], VTTPWRGD,
GTLREF[1:0], TCK, TDI, TRST#, TMS
Open Drain Signals3
3.
Signals that do not have RTT, nor are actively driven to their high-voltage level.
BSEL[2:0], VID[7:0], THERMTRIP#, FERR#/PBE#,
IERR#, BPM[5:0]#, BR0#, TDO, VTT_SEL, LL_ID[1:0],
MS_ID[1:0], GTLREF_SEL, VID_SELECT
Table 2-5. Signal Reference Voltages
GTLREF
VTT/2
BPM[5:0]#, LINT0/INTR, LINT1/NMI, RESET#, BINIT#,
BNR#, HIT#, HITM#, MCERR#, PROCHOT#, BR0#,
A[35:0]#, ADS#, ADSTB[1:0]#, AP[1:0]#, BPRI#, D[63:0]#,
DBI[3:0]#, DBSY#, DEFER#, DP[3:0]#, DRDY#,
DSTBN[3:0]#, DSTBP[3:0]#, LOCK#, REQ[4:0]#, RS[2:0]#,
NOTES:
1.
EDRDY# and PC_REQ# are not features of the Celeron D processor in the 775-land package. They are included here for
future processor compatibility.
BOOTSELECT, VTTPWRGD, A20M#,
IGNNE#, INIT#, PWRG
OOD2, SMI#,
STPCLK#, TCK2, TDI2, TMS2, TRST#2 2.
These signals also have hysteresis added to the reference voltage. See
Table 2-12 for more information.