Notes On Use Of Prescaler - Fujitsu F2MC-8FX Hardware Manual

6.13

Notes on Use of Prescaler

This section gives notes on using the prescaler.
The prescaler uses the machine clock and timebase timer clock and operates continuously while these
clocks are running. Accordingly, the operations of individual peripheral resources immediately after they
are activated may involve an error of up to one cycle of the clock source captured by the resource,
depending on the prescaler output value.
Figure 6.13-1 Clock Capturing Error Immediately after Activation of Peripheral Resources
Prescaler output
Resource activation
Clock capturing
by resource
The prescaler count value affects the following resources:
• UART/SIO
• 8/16-bit composite timer
• 16-bit PPG
• 10-bit A/D converter
CHAPTER 6 CLOCK CONTROLLER
Clock capturing error
immediately after
resource activation
81