18.
FREQM – Frequency Meter
18.1. Overview
The Frequency Meter (FREQM) can be used to accurately measure the frequency of a clock by
comparing it to a known reference clock.
18.2. Features
•
Accurately measures a clock frequency
•
A selectable reference clock from GCLK_FREQM_REF sources
•
A selectable clock from GCLK_FREQM_MSR sources can be measured
•
Ratio can be measured with 24-bit accuracy
18.3. Block Diagram
Figure 18-1. FREQM Block Diagram
ENABLE
VALUE
REFNUM
INTFLAG
GCLK_FREQM_REF
GCLK_FREQM_MSR
DONE
START
COUNTER
TIMER
CLK_MSR
CLK_REF
EN
EN
18.4. Signal Description
Not applicable.
18.5. Product Dependencies
In order to use this peripheral, other parts of the system must be configured correctly, as described below.
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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