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4
Am486DE2 Microprocessor
Table of Contents
Distinctive Characteristics............................................................................................................................1
General Description......................................................................................................................................1
Block Diagram..............................................................................................................................................2
Ordering Information ....................................................................................................................................3
Connection Diagrams and Pin Designations................................................................................................7
168-Pin Grid Array (PGA) Package.......................................................................................................7
168-Pin PGA Designations (Functional Grouping) ................................................................................8
208-Lead Shrink Quad Flat Pack (SQFP) Package...............................................................................9
208-Lead SQFP Designations (Functional Grouping) .........................................................................10
Logic Symbol..............................................................................................................................................11
Pin Descriptions .........................................................................................................................................12
A20M....................................................................................................................................................12
A31–A2................................................................................................................................................12
ADS......................................................................................................................................................12
AHOLD (Modified)................................................................................................................................12
BE3–BE0 .............................................................................................................................................12
BLAST (Modified).................................................................................................................................12
BOFF ...................................................................................................................................................12
BRDY...................................................................................................................................................12
BREQ...................................................................................................................................................13
BS8/BS16 ............................................................................................................................................13
CACHE (New)......................................................................................................................................13
CLK (Modified).....................................................................................................................................13
D31–D0................................................................................................................................................13
D/C.......................................................................................................................................................13
DP3–DP0.............................................................................................................................................13
EADS (Modified)..................................................................................................................................13
FERR...................................................................................................................................................14
FLUSH (Modified)................................................................................................................................14
HITM (New)..........................................................................................................................................14
HLDA ...................................................................................................................................................14
HOLD...................................................................................................................................................14
IGNNE..................................................................................................................................................14
INTR.....................................................................................................................................................14
INV (New) ............................................................................................................................................14
KEN......................................................................................................................................................14
LOCK...................................................................................................................................................14
M/IO.....................................................................................................................................................15
NMI ......................................................................................................................................................15
PCD .....................................................................................................................................................15
PCHK...................................................................................................................................................15
PLOCK (Modified)................................................................................................................................15
PWT.....................................................................................................................................................15
RDY .....................................................................................................................................................15
RESET.................................................................................................................................................15
SMI (New)............................................................................................................................................15
SMIACT (New).....................................................................................................................................16
SRESET (New)....................................................................................................................................16
STPCLK (New) ....................................................................................................................................16
TCK......................................................................................................................................................16
TDI.......................................................................................................................................................16
TDO .....................................................................................................................................................16
TMS .....................................................................................................................................................16
UP........................................................................................................................................................16
VOLDET (New, 168-Pin PGA Package only) ......................................................................................16