Diff: serialdata.cpp

Revision:

0:9d530d56a118

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/serialdata.cpp	Sun Jul 24 14:42:26 2016 +0000
@@ -0,0 +1,73 @@
+#include <mbed.h>
+
+extern Serial pc;
+
+void serialSend(float v) {
+    pc.printf("aaaa"); // header
+    unsigned char* data = (unsigned char*) &v;
+    for (int i = 0; i < 4; i++) {
+      pc.putc(data[i]);
+    }
+    pc.printf("\r\n"); // end of line
+}
+
+void serialSendVec(float vec[], int length) {
+    pc.printf("aaaa"); // header
+    unsigned char* data = (unsigned char*) vec;
+    for (int i = 0; i < length*4; i++) {
+      pc.putc(data[i]);
+    }
+    pc.printf("\r\n"); // end of line
+
+}
+
+enum RecvState {
+    NONE,
+    HEADER, 
+    DATA, 
+    END
+};
+
+float serialRecv() {
+    RecvState state = NONE;
+    int headerStep = 0;
+    int dataStep = 0;
+    bool receiving = 1;
+    char buf[8];
+    float v = -10;
+    while(receiving) {
+        char c = pc.getc();
+        switch(state) {
+            case NONE:
+            case HEADER:
+                if(c == 'a') {
+                    headerStep++;
+                    if(headerStep == 4) {
+                        state = DATA;
+                        dataStep = 0;
+                        v = 0;
+                    }
+                } else {
+                    headerStep = 0;
+                }
+                break;
+            case DATA:
+                dataStep += 1;
+                buf[dataStep-1] = c;
+                if(dataStep == 4) {
+                  state = END;
+                  v = *(float*)buf;
+                }
+                break;
+            case END: 
+                if(c == '\r' && pc.getc() == '\n') {
+                  return v;
+                } else {
+                  state = NONE;
+                  headerStep = 0;
+                }
+                break;
+        }
+    }
+    return v;
+}