AT32UC3C2512C Automotive Atmel Corporation, AT32UC3C2512C Automotive Datasheet - Page 208

• Manufacturer Part Number: AT32UC3C2512C Automotive
• Manufacturer: Atmel Corporation

13. Frequency Meter (FREQM)
13.1
13.2
13.3
Figure 13-1. Frequency Meter Block Diagram
13.4
13.4.1
9166C–AVR-08/11
Features
Overview
Block Diagram
Product Dependencies
Power Management
REFSEL
CLKSEL
Rev: 3.1.0.1
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The Frequency Meter (FREQM) can be used to accurately measure the frequency of a clock by
comparing it to a known reference clock.
In order to use this module, other parts of the system must be configured correctly, as described
below.
The device can enter a sleep mode while a measurement is ongoing. However, make sure that
neither CLK_MSR nor CLK_REF is stopped in the actual sleep mode. FREQM interrupts can
wake up the device from sleep modes when the measurement is done, but only from sleep
modes where CLK_FREQM is running. Please refer to the Power Manager chapter for details.
Accurately measures a clock frequency
Selectable reference clock
A selectable clock can be measured
Ratio can be measured with 24-bit accuracy
CLK_MSR
CLK_REF
Counter
REFNUM,
Timer
START
START
VALUE
Trigger
ISR
AT32UC3C
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