Diff: main.cpp
- Revision:
- 0:958661d88e40
diff -r 000000000000 -r 958661d88e40 main.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Mon Oct 17 10:42:38 2011 +0000
@@ -0,0 +1,218 @@
+/*
+ * wave1: wave test generator
+ *
+ */
+
+#include "mbed.h"
+
+DigitalOut led1(LED1);
+//DigitalOut led2(LED2);
+//DigitalOut led3(LED3);
+//DigitalOut led4(LED4);
+
+DigitalOut osc1(p21);
+//PwmOut led1(LED1);
+
+Serial pc(USBTX,USBRX);
+
+Ticker oscTick1;
+
+// ---------------------------------------------------------------------------
+#if 1
+int oscData[] = { 1,1,1,0,0,0,0 };
+#endif
+#if 0
+// DMFM
+int oscData[] = { 0,1,1,0,0,0,0,1,1,1,0,0,0,1,1,0,0,0,0,1,1,1,0,0,
+ 1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,
+ 1,1,0,0,1,1,0,0,1,1,0,0,
+ 1,1,1,0,0,0,1,1,1,0,0,0
+ };
+#endif
+#if 0
+// Manchester
+int oscData[] = { 0,1,0,1,0,0,1,1,0,0,1,1,0,1,0,1,0,1,0,
+ 0,1,1,0,1,1,0,0,1,0,0,1,0,0,
+ };
+#endif
+
+const int dx_max = sizeof(oscData)/sizeof(oscData[0]);
+int dx = 0;
+
+// ---------------------------------------------------------------------------
+
+enum { RESET=0, SCRAMBLE, DESCRAMBLE };
+int scramble1(int b, int func) {
+ static int crc = 0; // 7 bit
+ int fb;
+ int op;
+
+ b = !!b;
+
+ fb = !!(crc & 0x40) ^ !!(crc & 0x08);
+ crc <<= 1;
+ op = b ^ fb;
+
+ switch(func) {
+ case SCRAMBLE:
+ crc |= op;
+ break;
+ case DESCRAMBLE:
+ crc |= b;
+ break;
+ case RESET:
+ op = 0;
+ crc = 0;
+ break;
+ } // switch - op
+
+ return !!op;
+
+} // scramble1
+
+// ---------------------------------------------------------------------------
+
+int nrz() {
+ static int c = 0;
+ static int b = 0;
+ static int op = 0;
+
+ if(c == 0) {
+ // bit start
+ b = scramble1(1,SCRAMBLE);
+ op = b; // set data
+ }
+ else {
+ // bit centre
+ // same data
+ }
+
+ if(++c > 1) c = 0;
+
+ return op;
+} // nrz
+
+int nrzi() {
+ static int c = 0;
+ static int b = 0;
+ static int op = 0;
+
+ if(c == 0) {
+ // bit start
+ b = scramble1(1,SCRAMBLE);
+ }
+ else {
+ // bit centre
+ if(b == 1) op = !op; // flip if 1
+ }
+
+ if(++c > 1) c = 0;
+
+ return op;
+} // nrzi
+
+int man() {
+ static int c = 0;
+ static int b = 0;
+ static int op = 0;
+
+ if(c == 0) {
+ // bit start
+ int d = rand()&1;
+ b = scramble1(d,SCRAMBLE);
+ op = !b; // setup for transition
+ }
+ else {
+ // bit centre
+ // transition: +ve=1, -ve=0
+ op = b; // transition direction represents bit sense
+ }
+
+ if(++c > 1) c = 0;
+
+ return op;
+} // man
+
+int dman() {
+ static int c = 0;
+ static int b = 0;
+ static int op = 0;
+
+ if(c == 0) {
+ // bit start
+ int d = rand()&1;
+ b = scramble1(d,SCRAMBLE);
+ if(b == 1) op = !op; // flip if 1
+ }
+ else {
+ // bit centre
+ op = !op; // flip always
+ }
+
+ if(++c > 1) c = 0;
+
+ return op;
+} // dman
+
+int dmfm() {
+ static int c = 0;
+ static int b = 0;
+ static int b1 = 0;
+ static int op = 0;
+
+
+ if(c == 0) {
+ // bit start
+ int d = rand()&1;
+ b = scramble1(d,SCRAMBLE);
+ if(b1 == 0 && b == 0) op = !op; // flip if 2 zeros
+ b1 = b;
+ }
+ else {
+ // bit centre
+ if(b == 1) op = !op; // flip if 1
+ }
+
+ if(++c > 1) c = 0;
+
+ return op;
+} // dmfm
+
+// ---------------------------------------------------------------------------
+
+void oscOut1() {
+ osc1 = man();
+ //osc1 = oscData[dx++];
+ if(dx >= dx_max) dx = 0;
+}
+
+// ---------------------------------------------------------------------------
+
+int main() {
+
+ scramble1(0,RESET);
+
+
+ osc1 = 0;
+ oscTick1.attach_us(&oscOut1, 500); // chip period
+
+
+// led1.period(1);
+// led1.write(50);
+
+ pc.printf("\n\rStart: wave1\n\r");
+
+ while (1) {
+ led1 = 1;
+ wait(0.25);
+ led1 = 0;
+ wait(0.25);
+//
+// pc.printf(".");
+//
+ } // while
+
+} // main
+
+// ---------------------------------------------------------------------------
+
gavin beardall