Frequency Counter Module - Silicon Laboratories Si4010 Software Programming Manual

7.5. Frequency Counter Module

This module is responsible for interfacing to the frequency counter (FC). See "AN526: Si4010 API Additional
Library Description" for more details
7.5.1. Frequency Counter Key Terms
Table 9 lists key terms used in describing the Frequency Counter (FC) module.
Term
Counter mode
Interval
Divider clock
7.5.2. Frequency Counter Module Functions
vFc_Setup
Description: Sets up the counter mode, divider selector and number of clock cycles in an
interval. It clears any previous frequency counter settings.
Inputs:
biFcCtrl: (BYTE) Select the counter mode and divider selector. The counter mode
is essentially the interval clock source. The table describes the purpose of each bit
in this input parameter.
Table 9. Frequency Counter Terms
Determined by the source for the interval clock.
Number of interval clock cycles during which divider clock
cycles are counted.
Input clock which is counted during the specified interval.
Bits
2:0 Counter Mode.
0: Off
1: Reference clock from GPIO3
2: Undivided LPOSC (24 MHz)
3: Divided LPOSC (system clock)
4: Crystal oscillator from GPIO0
5: Reserved
6: Sleep timer output
7: GPIO output pulse
5 Divider Clock.
Which clock is being counted during the interval:
0: LC Oscillator
1: Divider
Definition
Purpose
Rev. 1.0
AN370
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