1 files changed, 57 insertions, 0 deletions
diff --git a/sem4/embedded/emb_m2/myfloat_red.h b/sem4/embedded/emb_m2/myfloat_red.h
new file mode 100644
index 0000000..b553233
--- /dev/null
+++ b/sem4/embedded/emb_m2/myfloat_red.h
@@ -0,0 +1,57 @@
+/*
+  Low level precision floating point lib
+  Author: Henrik Schiøler
+*/
+
+//low precision floating pt type
+typedef struct myfloat
+{
+        signed char mantissa;
+        signed char exponent;
+} myfloat_type;
+
+
+//convert from double to low precision type
+void doub2mydouble(double arg, myfloat_type *res)
+{
+   int exponent;
+   double temp;
+   exponent = ceil(log(abs(arg))/log(2)); //base 2 logarithm
+   temp=arg*pow(2,7-exponent);
+   res->mantissa = (signed char)temp;
+   res->exponent = exponent-7;
+}
+
+//convert from low precision type to double
+double myfloat2double(myfloat_type *arg1)
+{
+  double res = (double)(arg1->mantissa) * pow(2,arg1->exponent);
+   return res;
+}
+
+//multiply to low precision types
+void mult_float(myfloat_type *arg1,myfloat_type *arg2,myfloat_type *result)
+{
+  int temp;
+  unsigned char sign;
+  
+  sign=0x80 & ((unsigned char)arg1-> mantissa ^ (unsigned char)arg2-> mantissa); //find sign of result 
+  
+  char i=0;
+   temp = (int)(arg1-> mantissa) * (int)(arg2-> mantissa);
+   
+   temp = temp & 0x7f00; //take away sign from product
+  
+   while(abs(temp)>128)
+   {
+      i++;
+      temp=temp>>1;
+   }
+   
+   result->mantissa = (unsigned char) temp;
+   
+   result->mantissa = result->mantissa | sign; //add recorded sign
+   
+   result->exponent = arg1->exponent + arg2->exponent + i;
+   
+}