AT89C51-12 ATMEL [ATMEL Corporation], AT89C51-12 Datasheet - Page 11

• Manufacturer Part Number: AT89C51-12
• Description: 8-Bit Microcontroller with 4K Bytes Flash
• Manufacturer: ATMEL [ATMEL Corporation]

External Program Memory Read Cycle
External Data Memory Read Cycle
PORT 0
PORT 2
PORT 0
PORT 2
PSEN
PSEN
ALE
ALE
RD
A0 - A7 FROM RI OR DPL
t
LHLL
t
AVLL
t
AVLL
t
P2.0 - P2.7 OR A8 - A15 FROM DPH
LHLL
t
AVWL
t
LLAX
t
AVDV
A0 - A7
t
LLAX
t
LLWL
t
t
RLAZ
LLPL
t
t
LLDV
AVIV
A8 - A15
t
PLAZ
t
RLRH
t
RLDV
DATA IN
t
t
PLIV
LLIV
INSTR IN
t
PXIX
t
PXIZ
t
A0 - A7 FROM PCL
t
t
RHDZ
t
t
PLPH
PXAV
RHDX
WHLH
A8 - A15 FROM PCH
A8 - A15
A0 - A7
INSTR IN
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