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Si5351 Simple Sweep Generator
/*
Si5351 Simple Sweep Generator
connect Si5351 to I2C
Sweep out is on pin 5, ranging from 0-5V (3.3V).
Use a filter on sweep out voltage. 100K + 1uF should be a good start.
A op-amp can be used to improve the filtering of the DC voltage.
Copyright (c) 2016 Thomas S. Knutsen <la3pna@gmail.com>
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject
to the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
int correction = 0; // use the Si5351 correction sketch to find the frequency correction factor
int inData = 0;
long steps = 100;
unsigned long startFreq = 10000000;
unsigned long stopFreq = 100000000;
int analogpin = 5;
int delaytime = 50;
#include <si5351.h>
#include "Wire.h"
Si5351 si5351;
void setup() {
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0);
si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_6MA);
si5351.set_correction(correction);
info();
}
void info(){
Serial.println("Si5351 sweeper");
Serial.println("A = Start frequency");
Serial.println("B = Stop frequency");
Serial.println("S = Stepsize");
Serial.println("M = single sweep");
Serial.println("C = continious sweep untill Q");
Serial.println("T = timestep in ms, currently 50.");
}
void loop() {
inData = 0;
if (Serial.available() > 0) // see if incoming serial data:
{
inData = Serial.read(); // read oldest byte in serial buffer:
}
if (inData == 'M') {
inData = 0;
unsigned long freqstep = (stopFreq - startFreq) / steps ;
for (int i = 0; i < (steps+1); i++ ) {
unsigned long freq = startFreq + (freqstep*i);
si5351.set_freq(freq*100ULL, 0, SI5351_CLK0);
analogWrite(analogpin, map(i, 0, steps,0,255));
delay(delaytime);
}
}
if (inData == 'C'){
boolean runing = true;
inData = 0;
while(runing){
unsigned long freqstep = (stopFreq - startFreq) / steps ;
for (int i = 0; i < (steps+1); i++ ) {
unsigned long freq = startFreq + (freqstep*i);
si5351.set_freq(freq*100ULL, 0, SI5351_CLK0);
analogWrite(analogpin, map(i, 0, steps,0,255));
delay(delaytime);
if (Serial.available() > 0) // see if incoming serial data:
{
inData = Serial.read(); // read oldest byte in serial buffer:
if (inData == 'Q'){
runing = false;
inData = 0;
}
}
}
}
}
if (inData == 'S') {
steps = Serial.parseInt();
Serial.print("Steps: ");
Serial.println(steps);
inData = 0;
}
if (inData == 'H'){
info();
}
if (inData == 'T'){
delaytime = Serial.parseInt();
Serial.print("time pr step: ");
Serial.println(delaytime);
inData = 0;
}
if (inData == 'L') {
for (int i = 0; i < (steps+1); i++ ) {
// print out the value you read:
Serial.print(i*10);
Serial.print(';');
Serial.print(steps);
Serial.print(';');
Serial.println(-i);
delay(10); // delay in between reads for stability
}
inData = 0;
}
if (inData == 'A') {
startFreq = Serial.parseInt();
Serial.print("Start: ");
Serial.println(startFreq);
inData = 0;
}
if (inData == 'B') {
stopFreq = Serial.parseInt();
Serial.print("Stop: ");
Serial.println(stopFreq);
inData = 0;
}
}
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