Electronics America 8-Bit Single-Chip Microcontrollers User's Manual

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CHAPTER 7 CLOCK GENERATOR
The fastest instruction of the µ PD78054 and 78054Y Subseries is executed with two clocks of the CPU clock.
Therefore, relationships between the CPU clock (fCPU) and the minimum instruction execution time are as shown in
Table 7-2.
Table 7-2. Relationship between CPU Clock and Minimum Instruction Execution Time
CPU Clock (fCPU) Minimum Instruction Execution Time: 2/fCPU
fX 0.4 µ s
fX/2 0.8 µ s
fX/2
2
1.6 µ s
fX/2
3
3.2 µ s
fX/2
4
6.4 µ s
fX/2
5
12.8 µ s
fXT/2 122 µ s
Remarks 1. fX = 5.0 MHz, fXT = 32.768 kHz
2. fX : Main system clock oscillation frequency
3. f
XT : Subsystem clock oscillation frequency