Alan Matheson / Mbed 2 deprecated AD9850

A port of AD9850/51 code from Arduino source. This port allows direct input of the frequency in Mega Hertz rather than a series of Hex digits as in Liam Goudges program.

Dependencies:   mbed

main.cpp@0:bea0000c5526, 2014-02-09 (annotated)

Committer:
alan_matheson
Date:
Sun Feb 09 23:13:55 2014 +0000
Revision:
0:bea0000c5526
Child:
1:44d13dabc8e9
Initial port of AD9850 program from Arduino

Who changed what in which revision?

UserRevisionLine numberNew contents of line
alan_matheson 0:bea0000c5526 1 #include "mbed.h"
alan_matheson 0:bea0000c5526 2
alan_matheson 0:bea0000c5526 3 /*
alan_matheson 0:bea0000c5526 4 * A simple single freq AD9850 Arduino test script
alan_matheson 0:bea0000c5526 5 * Original AD9851 DDS sketch by Andrew Smallbone at www.rocketnumbernine.com
alan_matheson 0:bea0000c5526 6 * Modified for testing the inexpensive AD9850 ebay DDS modules
alan_matheson 0:bea0000c5526 7 * Pictures and pinouts at nr8o.dhlpilotcentral.com
alan_matheson 0:bea0000c5526 8 * 9850 datasheet at http://www.analog.com/static/imported-files/data_sheets/AD9850.pdf
alan_matheson 0:bea0000c5526 9 * Use freely
alan_matheson 0:bea0000c5526 10 */
alan_matheson 0:bea0000c5526 11
alan_matheson 0:bea0000c5526 12
alan_matheson 0:bea0000c5526 13 //efine W2_CLK // connect to AD9850 module2 word load clock pin (CLK)
alan_matheson 0:bea0000c5526 14 //efine W1_CLK 12 // connect to AD9850 module1 word load clock pin (CLK)
alan_matheson 0:bea0000c5526 15 //efine FQ_UD p5 // connect to freq update pin (FQ)
alan_matheson 0:bea0000c5526 16 //efine DATA 10 // connect to serial data load pin (DATA)
alan_matheson 0:bea0000c5526 17 //efine RESET 9 // connect to reset pin (RST).
alan_matheson 0:bea0000c5526 18
alan_matheson 0:bea0000c5526 19 #define pulseHigh(pin) {pin = 1; pin = 0; }
alan_matheson 0:bea0000c5526 20
alan_matheson 0:bea0000c5526 21
alan_matheson 0:bea0000c5526 22
alan_matheson 0:bea0000c5526 23 // configure data pins for output
alan_matheson 0:bea0000c5526 24 DigitalOut FQ_UD(p8);
alan_matheson 0:bea0000c5526 25 DigitalOut W_CLK(p7);
alan_matheson 0:bea0000c5526 26 DigitalOut DATA(p5);
alan_matheson 0:bea0000c5526 27 DigitalOut RESET(p15);
alan_matheson 0:bea0000c5526 28
alan_matheson 0:bea0000c5526 29
alan_matheson 0:bea0000c5526 30
alan_matheson 0:bea0000c5526 31
alan_matheson 0:bea0000c5526 32 // transfers a byte, a bit at a time, LSB first to the 9850 via serial DATA line
alan_matheson 0:bea0000c5526 33 void tfr_byte_module1(char data)
alan_matheson 0:bea0000c5526 34 {
alan_matheson 0:bea0000c5526 35 for (int i=0; i<8; i++, data>>=1) {
alan_matheson 0:bea0000c5526 36 DATA = (data & 0x01);
alan_matheson 0:bea0000c5526 37 pulseHigh(W_CLK); //after each bit sent, CLK is pulsed high
alan_matheson 0:bea0000c5526 38 }
alan_matheson 0:bea0000c5526 39 }
alan_matheson 0:bea0000c5526 40
alan_matheson 0:bea0000c5526 41 void tfr_byte_module2(char data)
alan_matheson 0:bea0000c5526 42 {
alan_matheson 0:bea0000c5526 43 for (int i=0; i<8; i++, data>>=1) {
alan_matheson 0:bea0000c5526 44 DATA = (data & 0x01);
alan_matheson 0:bea0000c5526 45 pulseHigh(W_CLK); //after each bit sent, CLK is pulsed high
alan_matheson 0:bea0000c5526 46 }
alan_matheson 0:bea0000c5526 47 }
alan_matheson 0:bea0000c5526 48
alan_matheson 0:bea0000c5526 49
alan_matheson 0:bea0000c5526 50 // frequency calc from datasheet page 8 = <sys clock> * <frequency tuning word>/2^32
alan_matheson 0:bea0000c5526 51 void sendFrequency(double frequency) {
alan_matheson 0:bea0000c5526 52 int32_t freq = frequency *1e6 * 4294967295/125000000; // note 125 MHz clock on 9850
alan_matheson 0:bea0000c5526 53 for (int b=0; b<4; b++, freq>>=8) {
alan_matheson 0:bea0000c5526 54 tfr_byte_module1(freq & 0xFF);
alan_matheson 0:bea0000c5526 55 }
alan_matheson 0:bea0000c5526 56 tfr_byte_module1(0X38); // Final control byte, all 0 for 9850 chip
alan_matheson 0:bea0000c5526 57 }
alan_matheson 0:bea0000c5526 58
alan_matheson 0:bea0000c5526 59
alan_matheson 0:bea0000c5526 60 int main()
alan_matheson 0:bea0000c5526 61 {
alan_matheson 0:bea0000c5526 62 double frequency;
alan_matheson 0:bea0000c5526 63
alan_matheson 0:bea0000c5526 64 // Initialise the AD9850 module
alan_matheson 0:bea0000c5526 65 pulseHigh(RESET);
alan_matheson 0:bea0000c5526 66 pulseHigh(W_CLK);
alan_matheson 0:bea0000c5526 67 pulseHigh(FQ_UD); // this pulse enables serial mode - Datasheet page 12 figure 10
alan_matheson 0:bea0000c5526 68
alan_matheson 0:bea0000c5526 69
alan_matheson 0:bea0000c5526 70
alan_matheson 0:bea0000c5526 71
alan_matheson 0:bea0000c5526 72
alan_matheson 0:bea0000c5526 73 while(1)
alan_matheson 0:bea0000c5526 74 {
alan_matheson 0:bea0000c5526 75 frequency = 10.0034;
alan_matheson 0:bea0000c5526 76 {
alan_matheson 0:bea0000c5526 77 sendFrequency(frequency);
alan_matheson 0:bea0000c5526 78 pulseHigh(FQ_UD);
alan_matheson 0:bea0000c5526 79 wait(5.0);
alan_matheson 0:bea0000c5526 80 }
alan_matheson 0:bea0000c5526 81 }
alan_matheson 0:bea0000c5526 82
alan_matheson 0:bea0000c5526 83 }
alan_matheson 0:bea0000c5526 84
alan_matheson 0:bea0000c5526 85