IC80C51
IC80C31
TIMING WAVEFORMS
t
LHLL
ALE
t
LLPL
t
PLPH
PLIV
t
AVLL
t
PSEN
t
PLAZ
tPXIZ
t
LLAX
A7-A0
t
PXIX
PORT 0
INSTR IN
A7-A0
t
LLIV
AVIV
A15-A8
t
A15-A8
PORT 2
Figure 28. External Program Memory Read Cycle
ALE
t
WHLH
PSEN
t
LLDV
t
LLWL
tRLRH
RD
t
AVLL
t
RLAZ
LLAX
t
RHDZ
t
RLDV
t
t
RHDX
PORT 0
A7-A0 FROM RI OR DPL
DATA IN
A7-A0 FROM PCL
INSTR IN
t
AVWL
t
AVDV
A15-A8 FROM DPH
A15-A8 FROM PCH
PORT 2
Figure 29. External Data Memory Read Cycle
Integrated Circuit Solution Inc.
MC001-0B
41