Datasheet

DS80C320/DS80C323 High-Speed/Low-Power Microcontrollers
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EXTERNAL CLOCK CHARACTERISTICS
PARAMETER SYMBOL MIN TYP MAX UNITS
Clock High Time t
CHCX
10 ns
Clock Low Time t
CLCX
10 ns
Clock Rise Time t
CLCH
5 ns
Clock Fall Time t
CHCL
5 ns
SERIAL PORT MODE 0 TIMING CHARACTERISTICS
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SM2 = 0;
12 clocks per cycle
12t
CLCL
Serial Port Clock
Cycle Time
t
XLXL
SM2 = 1;
4 clocks per cycle
4t
CLCL
ns
SM2 = 0
12 clocks per cycle
10t
CLCL
Output Data Setup to
Clock Rising Edge
t
QVXH
SM2 = 1;
4 clocks per cycle
3t
CLCL
ns
SM2 = 0
12 clocks per cycle
2t
CLCL
Output Data Hold
from Clock Rising
t
XHQX
SM2 = 1;
4 clocks per cycle
t
CLCL
ns
SM2 = 0;
12 clocks per cycle
t
CLCL
Input Data Hold After
Clock Rising
t
XHDX
SM2 = 1;
4 clocks per cycle
t
CLCL
ns
SM2 = 0;
12 clocks per cycle
11t
CLCL
Clock Rising Edge to
Input Data Valid
t
XHDV
SM2 = 1
4 clocks per cycle
2t
CLCL
ns
EXPLANATION OF AC SYMBOLS
In an effort to remain compatible with the original 8051 family, this device specifies the same parameter as such
devices, using the same symbols. For completeness, the following is an explanation of the symbols.
t Time
A Address
C Clock
D Input data
H Logic level high
L Logic level low
I Instruction
P
PSEN
Q Output data
R
RD signal
V Valid
W
WR signal
X No longer a valid logic level
Z Tri-state