Rainbow Electronics AT89C51SND1C - Manual (Page 189)

189
AT8xC51SND1C
4109E–8051–06/03
Timings Test conditions: capacitive load on all pins= 50 pF.
Table 163. External IDE 16-bit Bus Cycle - Data Read AC Timings
V
DD
= 2.7 to 3.3 V, T
A
= -40 to +85
°
C
Table 164. External IDE 16-bit Bus Cycle - Data Write AC Timings
V
DD
= 2.7 to 3.3 V, T
A
= -40 to +85
°
C
Symbol Parameter
Variable Clock
Standard Mode
Variable Clock
X2 Mode
Unit Min Max Min Max
T
CLCL
Clock Period 50 50 ns
T
LHLL
ALE Pulse Width 2·T
CLCL
-15 T
CLCL
-15 ns
T
AVLL
Address Valid to ALE Low T
CLCL
-20 0.5·T
CLCL
-20 ns
T
LLAX
Address hold after ALE Low T
CLCL
-20 0.5·T
CLCL
-20 ns
T
LLRL
ALE Low to RD Low 3·T
CLCL
-30 1.5·T
CLCL
-30 ns
T
RLRH
RD Pulse Width 6·T
CLCL
-25 3·T
CLCL
-25 ns
T
RHLH
RD high to ALE High T
CLCL
-20 T
CLCL
+20 0.5·T
CLCL
-20 0.5·T
CLCL
+20 ns
T
AVDV
Address Valid to Valid Data In 9·T
CLCL
-65 4.5·T
CLCL
-65 ns
T
AVRL
Address Valid to RD Low 4·T
CLCL
-30 2·T
CLCL
-30 ns
T
RLDV
RD Low to Valid Data 5·T
CLCL
-30 2.5·T
CLCL
-30 ns
T
RLAZ
RD Low to Address Float 0 0 ns
T
RHDX
Data Hold After RD High 0 0 ns
T
RHDZ
Instruction Float After RD High 2·T
CLCL
-25 T
CLCL
-25 ns
Symbol Parameter
Variable Clock
Standard Mode
Variable Clock
X2 Mode
Unit Min Max Min Max
T
CLCL
Clock Period 50 50 ns
T
LHLL
ALE Pulse Width 2·T
CLCL
-15 T
CLCL
-15 ns
T
AVLL
Address Valid to ALE Low T
CLCL
-20 0.5·T
CLCL
-20 ns
T
LLAX
Address hold after ALE Low T
CLCL
-20 0.5·T
CLCL
-20 ns
T
LLWL
ALE Low to WR Low 3·T
CLCL
-30 1.5·T
CLCL
-30 ns
T
WLWH
WR Pulse Width 6·T
CLCL
-25 3·T
CLCL
-25 ns
T
WHLH
WR High to ALE High T
CLCL
-20 T
CLCL
+20 0.5·T
CLCL
-20 0.5·T
CLCL
+20 ns
T
AVWL
Address Valid to WR Low 4·T
CLCL
-30 2·T
CLCL
-30 ns
T
QVWH
Data Valid to WR High 7·T
CLCL
-20 3.5·T
CLCL
-20 ns
T
WHQX
Data Hold after WR High T
CLCL
-15 0.5·T
CLCL
-15 ns