NEC uPD78076 User Manual

Page of 627
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CHAPTER 7   CLOCK GENERATOR
The fastest instruction of the 
µ
PD78078 and 78078Y Subseries can be executed in two clocks of the CPU clock.
The relationship between the CPU clock (f
CPU
) and the minimum instruction execution time is shown in Table 7-2.
Table 7-2.  Relationship between CPU Clock and Minimum Instruction Execution Time
CPU Clock (f
CPU
)
Minimum Instruction Execution Time: 2/f
CPU
f
X
0.4 
µ
s
f
X
/2
0.8 
µ
s
f
X
/2
2
1.6 
µ
s
f
X
/2
3
3.2 
µ
s
f
X
/2
4
6.4 
µ
s
f
X
/2
5
12.8 
µ
s
f
XT
/2
122 
µ
s
f
X
 = 5.0 MHz, f
XT
 = 32.768 kHz
f
X
: Main system clock oscillation frequency
f
XT
: Subsystem clock oscillation frequency