MB95630H Series
MN702-00009-1v0-E
FUJITSU SEMICONDUCTOR LIMITED
59
CHAPTER 3 CLOCK CONTROLLER
3.10 Notes on Using Prescaler
3.10
Notes on Using Prescaler
This section provides notes on using the prescaler.
The prescaler operates with the machine clock and the clock generated from the time-base
timer, and keeps operating while those clocks are being supplied. Therefore, in the operation
immediately after a peripheral resource is started, an error of up to one cycle of the clock
source captured by that peripheral resource will occur, depending on the output value of the
prescaler.
Figure 3.10-1 Clock Capture Error Occurring Immediately after a Peripheral Function Starts
The prescaler count value affects the following peripheral functions:
•
8/16-bit composite timer
•
8/10-bit A/D converter
•
8/16-bit PPG
•
16-bit PPG timer
•
16-bit reload timer
•
UART/SIO dedicated baud rate generator
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