ADF4351 - BLUEPILL edition

SO2A STM32duino fork of https://github.com/olgierd/ADF4351

Usage

Check code. Use serial shortcuts to edit frequency, or adjust the follwing line in the code:

unsigned long long frequency = 2400000000; // 2.4GHz

Pinout connection

(warning: see note for cheaper smaller boards!)

ADF4351 <=> BluePill STM32Fxx
   DATA <=> PA7
   CLK  <=> PA5
    LE  <=> PA4 
  3.3V  <=> 3.3V
   GND  <=> GND

Serial USB adapter <=> BluePill STM32Fxx
   RX <=> PA9   (TX)
   TX <=> PA10  (RX)
   GND <=> GND

Cheap boards from Ali may have pin description swapped

On some boards, pins labels are swapped:

- Pin labaled "DATA" is actually CLK
- Pin labeled "CLK" is actually LE
- Pin labeled "LE" is actually DATA

Upstream Readme follows:

Code to control your ADF4351 board using Arduino. Written from scratch using official datasheet.

Pinout

Arduino pin #13 <-> CLK
Arduino pin #11 <-> DATA
Arduino pin #9 <-> LE

Use voltage dividers, ADF runs on 3.3V supply.
You can change LE pin assignment to any other IO pin.

Keyboard

x/c -/+ 10 Hz
s/d -/+ 100 Hz
w/e -/+ 1 kHz
2/3 -/+ 10 kHz
1/4 -/+ 100 kHz
5/6 -/+ 10 MHz
/ toggle RF output
+ increase RF power

Modifications

#define REF_CLK 25000000 - if you're using custom reference frequency, set it here

uint8_t slave_select_pin = 9; - this pin can be set to any other IO you like

unsigned long long frequency = 1000000000; that's a default frequency after power on

Set those two variables if you'd like to use this code for non-interactive operation (eg. LO for an upconverter):

uint8_t rf_ena = 1; // 0 - output disabled

uint8_t out_pwr = 0; // 0 - min, 3 - max

You can modify value of r_counter and clock_divider according to your needs. Decreasing step resolution will result in smaller phase noise.

Even when rf_ena is set to 0, the PLL is running and you can expect more than -50 dBm of signal at the output.

QO-100

I'm using this code to directly generate CW on QO-100, so the serial port output shows the downlink frequency (+10489000 kHz) in brackets:

FREQ: 2400060100 ( 560.50 )

rafal-rozestwinski/ADF4351-stm32