Intel 80386 - Page 279

DRAM PAL DESCRIPTIONS
PALl6R4 PAL DESIGN SPECIFICATIONS
PART NUMBER: 2-CLK DRAM CONTROL PAL
DRAM CONTROL PAL OF INTERLEAVED DRAM CONTROLLER FOR 80386 SYSTEMS
INTEL, SANTA CLARA, CALIFORNIA
CLK2 CLK BEO BEl BE2 BE3 W%R ROWSEL DISABLE GND
OE CASO CASI DT%R DEN RDY WE CAS2 CAS3 VCC
/CASO = /ROWSEl * /DT%R * CLK * /DlSABlE ;drop CAS on read
+ /ROWSEL * /DT%R * /DEN ;maintain CAS on read
+ /ROWSEl * /DEN * /BEO * /DISABlE ;activate CAS on write
; BEx must be ma i nta i ned throughout
;DISABlE must be maintained through last /ROWSEL * CLK
/CASl = /ROWSEL * /DT%R * CLK * /DISABLE
+ /ROWSEL * /DT%R * /DEN
+ /ROWSEL * /DEN * /BEI * /DISABLE
/CAS2 = /ROWSEL * /DT%R * CLK * /DISABLE
+ /ROWSEL * /DT%R * /DEN
+ /ROWSEL * /DEN * /BE2 * /DISABLE
/CAS3 = /ROWSEL * /DT%R * CLK * /DISABLE
+ /ROWSEL * /DT%R * /DEN
+ /ROWSEL * /DEN * /BE3 * /DISABLE
;drop CAS on read
;maintain CAS on read
;activate CAS on write
;drop CAS on read
;maintain CAS on read
;activate CAS on write
; drop CAS on read
;maintain CAS on read
;activate CAS on write
/DT%R:= ROWSEL * DEN * /W%R
+ /ROWSEL * /DT%R
; samp 1 e W%R when /ROWSEl * DEN
;otherwise: maintain state
+ /DEN * /DT%R
/DEN.- ClK * /ROWSEL * /DISABlE
+ /CLK * /DEN
;when elK: sample ROWSEL
;otherwise: maintain state
/WE:= /ROWSEL * DT%R * RDY * /DISABLE ;only drops for writes
/RDY := /ROWSEl * /DT%R * /DISABLE * elK ;drop RDY immediately for read
+ /WE * eLK ;drop RDY 1 ater for write
+ /RDY * /DEN ;ma i ntai n RDY
Figure C-5. 2-CLK DRAM Control PAL Equations
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