14.1 Overview Of Peripheral Control Clock Output; Table 14.1-1 Peripheral Control Clock Output Frequencies - Fujitsu F2MC-8L Series Hardware Manual

CHAPTER 14 PERIPHERAL CONTROL CLOCK OUTPUT

14.1 Overview of Peripheral Control Clock Output

The peripheral control clock output offers a choice of three clock signals different in
frequency.
Clock Output Function
The clock output function outputs clock signals (square waves) for driving, for example, a
peripheral LSI.
• The peripheral control clock register (SCGC) is used to enable clock output and select the
clock output frequency.
• The clock output function outputs one of the three clock signals different in frequency.
Table 14.1-1 lists the clock output frequencies and their respective divisors used by the
prescaler.

Table 14.1-1 Peripheral Control Clock Output Frequencies

Clock oscillation frequency
32.768 kHz (F
4.2 MHz (F
F : Subclock oscillation frequency
CL
F : Main clock oscillation frequency
CH
Check:
• The main clock stops oscillation in main-stop and subclock modes. The subclock stops
oscillation in sub-stop mode. Since the peripheral control clock output is also stopped when
clock oscillation stops, pay attention to the operations of the connected peripheral LSI when
entering any of these modes.
• This function is optional to the MB89121. Specify whether to use or not at the time of data
release.
296
Clock output frequency
)
CL
)
CH
16.384 kHz
131.25 kHz
175 kHz
Divided by:
2
32
24