SonicMEMS@Cornell
Control AD8933 waveform generator chip from mBed interfacing with MATLAB
Dependencies: mbed
Revision 0:15b3f9279b88, committed 2014-07-07
- Comitter:
- pc445
- Date:
- Mon Jul 07 02:03:22 2014 +0000
- Commit message:
- communication with Matlab
Changed in this revision
| main.cpp | Show annotated file Show diff for this revision Revisions of this file |
| mbed.bld | Show annotated file Show diff for this revision Revisions of this file |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Mon Jul 07 02:03:22 2014 +0000
@@ -0,0 +1,166 @@
+/////////////////////////////////////////////////////////////////////////
+// AD9833 control code
+// Create by Po-Cheng Chen 07-04-2014
+// Version 0.2 (MATLAB)
+/////////////////////////////////////////////////////////////////////////
+
+#include "mbed.h"
+#include "SPI.h"
+#include "DigitalOut.h"
+
+SPI AD9833_SPI(p5, p6, p7); //mosi, miso, sclk --> don't need MISO
+DigitalOut fSync(p8); //use p8 as FSync data pin (same as chip select)
+
+Serial pc(USBTX, USBRX); //define serial USB port
+DigitalOut myled1(LED1), myled2(LED2), myled3(LED3), myled4(LED4); //define LEDs
+
+/////////////////////////////////////////////////////////////////////////
+// ASCII to Interger function
+/////////////////////////////////////////////////////////////////////////
+unsigned int ascii2int(char c)
+{
+ unsigned int i;
+ i = 0;
+ switch(c) {
+ case 0x20:
+ i = 0;
+ break;
+ case '0' :
+ i = 0;
+ break;
+ case '1' :
+ i = 1;
+ break;
+ case '2' :
+ i = 2;
+ break;
+ case '3' :
+ i = 3;
+ break;
+ case '4' :
+ i = 4;
+ break;
+ case '5' :
+ i = 5;
+ break;
+ case '6' :
+ i = 6;
+ break;
+ case '7' :
+ i = 7;
+ break;
+ case '8' :
+ i = 8;
+ break;
+ case '9' :
+ i = 9;
+ break;
+ default:
+ i = 0;
+ break;
+ }
+ return i;
+}
+/////////////////////////////////////////////////////////////////////////
+// 8 digit function
+/////////////////////////////////////////////////////////////////////////
+unsigned int digit8(char c7, char c6, char c5, char c4,
+ char c3, char c2, char c1, char c0)
+{
+ unsigned int k7 = 10000000*ascii2int(c7);
+ unsigned int k6 = 1000000*ascii2int(c6);
+ unsigned int k5 = 100000*ascii2int(c5);
+ unsigned int k4 = 10000*ascii2int(c4);
+ unsigned int k3 = 1000*ascii2int(c3);
+ unsigned int k2 = 100*ascii2int(c2);
+ unsigned int k1 = 10*ascii2int(c1);
+ unsigned int k0 = ascii2int(c0);
+ unsigned int k = k7 + k6 + k5 + k4 + k3 + k2 + k1 + k0;
+ return k;
+}
+/////////////////////////////////////////////////////////////////////////
+// SPI initialization
+/////////////////////////////////////////////////////////////////////////
+void SPI_INITIALIZATION()
+{
+ //Setup the spi for 16 bit data, with 25MHz clock rate, mode 2
+ // Note: mBed is MSB first SPI protocol
+ AD9833_SPI.format(16,2);
+ AD9833_SPI.frequency(25000000);
+ fSync = 1;
+ wait_ms(10);
+}
+/////////////////////////////////////////////////////////////////////////
+// SPI writing
+/////////////////////////////////////////////////////////////////////////
+void write_SPI(short dat)
+{
+ fSync = 0;
+ AD9833_SPI.write(dat);
+ fSync = 1;
+}
+/////////////////////////////////////////////////////////////////////////
+// Calculate desired frequency
+/////////////////////////////////////////////////////////////////////////
+long calFreq(long freq)
+{
+ long freq_cal; //define freq calculated value
+ float freq_val = 0.00000000; //define ferq calculate tempotary value
+
+ //calculate the frqe reg value
+ //((desired frequency)/(reference frequency)) x 0x10000000.
+ freq_val = (((float)(freq))/25000000);
+ freq_cal = freq_val*0x10000000;
+ return freq_cal;
+}
+/////////////////////////////////////////////////////////////////////////
+// Set frequency register
+/////////////////////////////////////////////////////////////////////////
+void setFreq(long frequency)
+{
+ int freq_MSB; //define freq MSB reg value
+ int freq_LSB; //define freq LSB reg value
+
+ long freq_cal = calFreq(frequency); //calculate the frequency register
+
+ freq_MSB = (int)((freq_cal & 0xFFFC000)>>14); // shift 14 bits
+ freq_LSB = (int)(freq_cal & 0x3FFF);
+
+ freq_MSB = freq_MSB | 0x4000; //assign freq reg address
+ freq_LSB = freq_LSB | 0x4000;
+ ///////////////////////////////////////////////////////////////////////////////////
+ //print the data from the serial port to verifiy the function
+ //printf("freq_LSB 0x%x\n\r", freq_LSB);
+ //printf("freq_MSB 0x%x\n\r", freq_MSB);
+ ///////////////////////////////////////////////////////////////////////////////////
+ write_SPI(0x2100); //write control reg - apply reset
+ write_SPI(freq_LSB); //write freq reg - LSB
+ write_SPI(freq_MSB); //write freq reg - MSB
+ write_SPI(0xC000); //write phase reg - (0 for now)
+ write_SPI(0x2000); //write control reg - disable reset
+}
+
+/////////////////////////////////////////////////////////////////////////
+// Main function
+// Comments:include the command line from Matlab
+// Control from COM port
+/////////////////////////////////////////////////////////////////////////
+int main()
+{
+ char buf[128]; // assign buffer for the command from PC
+ SPI_INITIALIZATION(); // initialized the SPI
+ while(true) {
+ if (pc.readable()) {
+ //WAV AAAA BBBB CCCC DDDD EEEE FFFF GGGG HHHH END \n \0
+ //A, B, C, D ,E, F, G, H are frequency numbers
+ //need 3 + (32) + 3 + 1 + 1 = 40
+ pc.gets(buf, 16);
+ if ((buf[0] == 'W')&&(buf[1] == 'A')&&(buf[2] == 'V')&&(buf[11] == 'E')&&(buf[12] == 'N')&&(buf[13] == 'D')) {
+ myled1 = !myled1;
+ int freq_pc = digit8(buf[3], buf[4], buf[5], buf[6], buf[7], buf[8], buf[9], buf[10]);
+ setFreq(freq_pc);
+
+ } // end of if( buffer read)
+ } // end of if(pc.readable())
+ }// end of while()
+} // end of main()
\ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Mon Jul 07 02:03:22 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/024bf7f99721 \ No newline at end of file