Revision 0:e4b2af8e875a, committed 2010-07-22

Comitter:

smpedi

Date:

Thu Jul 22 14:24:52 2010 +0000

Commit message:

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SigGen.cpp	Thu Jul 22 14:24:52 2010 +0000
@@ -0,0 +1,184 @@
+#include "mbed.h"
+
+#define MAXWAVEPTS 20
+#define SQUARE      0
+#define SINE        1
+#define UP          65
+#define DOWN        66
+#define RIGHT       67
+#define LEFT        68
+
+AnalogOut wave(p18);
+Ticker  timer;
+float   wValue;
+float   waveVals[MAXWAVEPTS];
+float   *fpW, *fpEnd;
+float   fAmp, fModAmp;
+short   itype;
+
+void init_wave(int, int);
+void write_wavePt();
+int DoTermIO(char);
+void    ChangeRate(float);
+extern float input_control();
+extern void ledOut(int);
+
+DigitalOut  oled(p8);
+Serial pc(USBTX, USBRX); // tx, rx
+
+int main() {
+    float   rate, delay;
+    unsigned int    idelay;
+    char    c;
+
+    fAmp = 0.606f;
+    fModAmp = 0.5f;
+    pc.printf("\fFrequency (Hz)? ");
+    pc.scanf("%f",&rate);
+    if (rate > 2000.0f) rate = 2000.0f;
+    pc.printf("\n%f Hz, Got it\nSine (1) or Square? (0)",rate);
+    pc.scanf("%c",&c);
+    itype = c - 48;
+    pc.printf("\nType is %s \n",(itype ? "Sine" : "Square"));
+
+    delay = 1000000 / rate;                   // delay for one cycle
+    delay = delay / (float)(MAXWAVEPTS - 1);  // delay per point
+    idelay = (int)(delay);                    // delay in int format
+    init_wave((int)MAXWAVEPTS, itype);
+
+    pc.printf("\nrate = %f\n",rate);
+    pc.printf("delay = %f\n",delay);
+    pc.printf("idelay = %u micro-seconds\n",idelay);
+
+    timer.attach_us(&write_wavePt,idelay);
+    oled = 0;
+    while (1) {
+        switch (DoTermIO(pc.getc())) {
+            case    'i':
+                fModAmp *= 1.01;
+                if (fModAmp > 1.0)
+                   fModAmp = 1.0;
+                init_wave((int)MAXWAVEPTS, itype);
+                break;
+            case    'd':
+                fModAmp *= 0.99;
+                if (fModAmp < 0.05)
+                   fModAmp = 0.05;
+                init_wave((int)MAXWAVEPTS, itype);
+               break;
+                
+            case    UP:
+                rate +=  1.0f;
+                ChangeRate(rate);
+                break;
+            case    DOWN:
+                rate -=  1.0f;
+                ChangeRate(rate);
+                break;
+            case    RIGHT:
+                rate += 25.0f;
+                ChangeRate(rate);
+                break;
+            case    LEFT:
+                rate -=  25.0f;
+                ChangeRate(rate);
+                break;
+            case    -1:
+                pc.printf("%c",12);
+                break;
+        }
+    }
+}
+
+int DoTermIO(char c) {
+    char    e;
+    
+    if (c==17)
+        return(-1);
+        
+    if (c == 27) {      // escape sequence?
+        e = pc.getc();
+        if (e != 91) {
+            return((int)(-1));
+        }
+        pc.printf("%c",c);
+        return((int)(pc.getc()));
+    }
+    pc.putc(c);
+    return((int)c);
+}
+
+
+void ChangeRate(float val) {
+    int idelay;
+    float   delay;
+    
+    pc.printf("\f");
+    pc.printf(" FFreq = %8.0f",val);
+
+    delay = 1000000 / val;                   // delay for one cycle
+    delay = delay / (float)(MAXWAVEPTS - 1);  // delay per point
+    idelay = (int)(delay);                    // delay in int format
+
+    pc.printf("\nrate = %f\n",val);
+    pc.printf("delay = %f\n",delay);
+    pc.printf("idelay = %u micro-seconds\n",idelay);
+    timer.detach();
+    timer = Ticker();
+    timer.attach_us(&write_wavePt,idelay);
+}
+
+
+void write_wavePt
+
+    if (fpW >= fpEnd) {
+        fpW = waveVals;
+    }
+    wave.write(*fpW);
+}
+
+/* load wave array with values.  Currently supports square and sine, but any
+   arbitrary wave shape can be defined, as long as it is MAXWAVEPTS long
+*/
+
+void init_wave(int iNumPts, int itype) {       
+    int i, iMid;
+    float   fddeg, fdeg, pi;
+    float   *fp;
+    float   amp;
+
+    amp = fAmp * fModAmp;
+    switch (itype) {
+        case    SQUARE:          // square
+            iMid = iNumPts/2-1;
+            fpW = waveVals;
+            fp = fpW;
+            for (i=0; i<iMid; i++) {
+                *fp = 0.0;
+                fp++;
+            }
+            for (i=iMid; i< iNumPts; i++) {
+                *fp = amp * 2;
+                fp++;
+            }
+            fpEnd = fp-1;
+            break;
+
+        case    SINE:          // sine
+            pi = 3.1415926;
+            fddeg = ((2.0f * pi) / (float)iNumPts);
+            fpW = waveVals;
+            fp = fpW;
+            fdeg = 0;
+            for (i=0; i<iNumPts; i++) {
+                *fp =( amp * cos(fdeg)) + amp;
+                fp++;
+                fdeg += fddeg;
+            }
+            fpEnd = fp-1;
+
+            break;
+    }
+
+}
+

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Thu Jul 22 14:24:52 2010 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/e6be4cd80aad