Diff: MPL115A1/MPL115A1.cpp

Revision:

3:78ceda8ef565

Parent:

1:326ce5e200fb

Child:

4:634796e5b8c3

--- a/MPL115A1/MPL115A1.cpp	Wed Dec 13 09:46:08 2017 +0000
+++ b/MPL115A1/MPL115A1.cpp	Fri Mar 02 12:37:27 2018 +0000
@@ -1,107 +1,116 @@
 #include "MPL115A1.h"
 
-float get_a0(uint16_t a0);
-float get_b1(uint16_t b1);
-float get_c1(uint16_t c1);
-float get_c12(uint16_t c12);
+#define a0FracBits  3
+#define b1FracBits  13
+#define b2FracBits  14
+#define c12FracBits 22
+#define a0FracMask  0x0007
+#define b1FracMask  0x1FFF
+#define b2FracMask  0x3FFF
+#define c12FracMask 0x1FFF
+
+float getA0(uint16_t a0);
+float getB1(uint16_t b1);
+float getC1(uint16_t c1);
+float getC12(uint16_t c12);
 float getPressure();
 
 MPL115A1::MPL115A1(SPI &spi, NRF52_DigitalOut &cs) : spi(spi), cs(cs) {}
 
-float get_a0(uint16_t a0){
-    float temp_a0;
-    float temp_frac;
-    int temp_a0_int;
-    uint8_t negative_flag = 0;
+float getA0(uint16_t a0){
+    float tempA0;
+    float tempFrac;
+    int tempA0Int;
+    uint8_t negativeFlag = 0;
     
     if(a0 & 0x8000){
         a0 ^= 0xFFFF;   // Transform from 2's complement
         a0 -= 1;
-        negative_flag = 1;
+        negativeFlag = 1;
     }
     
-    temp_a0_int = a0 & 0x7FF8;
-    temp_a0_int = temp_a0_int >> a0_frac_bits;
+    tempA0Int = a0 & 0x7FF8;
+    tempA0Int = tempA0Int >> a0FracBits;
     
-    temp_a0 = temp_a0_int * 1.0;    // Int part
-    temp_frac = (1.0/(1<<3));
-    temp_frac *= (a0 & a0_frac_mask);
-    temp_a0 = temp_a0 + temp_frac;
+    tempA0 = tempA0Int * 1.0;    // Int part
+    tempFrac = (1.0/(1<<3));
+    tempFrac *= (a0 & a0FracMask);
+    tempA0 = tempA0 + tempFrac;
     
-    if(negative_flag) temp_a0 = -temp_a0;
+    if(negativeFlag) tempA0 = -tempA0;
     
-    return temp_a0;
+    return tempA0;
 }
 
-float get_b1(uint16_t b1){
-    float temp_b1;
-    float temp_frac;
-    int temp_b1_int;
-    uint8_t negative_flag = 0;
+float getB1(uint16_t b1){
+    float tempB1;
+    float tempFrac;
+    int tempB1Int;
+    uint8_t negativeFlag = 0;
     
     if (b1 & 0x8000){
         b1 ^= 0xFFFF;
         b1 -= 1;
-        negative_flag = 1;
+        negativeFlag = 1;
     }
     
-    temp_b1_int = b1 & 0x6000;
-    temp_b1_int = temp_b1_int >> b1_frac_bits;
+    tempB1Int = b1 & 0x6000;
+    tempB1Int = tempB1Int >> b1FracBits;
     
-    temp_b1 = temp_b1_int * 1.0;
-    temp_frac = (b1 & b1_frac_mask) * (1.0/(1<<b1_frac_bits));
-    temp_b1 = temp_b1 + temp_frac;
+    tempB1 = tempB1Int * 1.0;
+    tempFrac = (b1 & b1FracMask) * (1.0/(1<<b1FracBits));
+    tempB1 = tempB1 + tempFrac;
     
-    if(negative_flag) temp_b1 = -temp_b1;
+    if(negativeFlag) tempB1 = -tempB1;
     
-    return temp_b1;
+    return tempB1;
 }
 
-float get_b2(uint16_t b2){
-    float temp_b2;
-    float temp_frac;
-    int temp_b2_int;
-    uint8_t negative_flag = 0;
+float getB2(uint16_t b2){
+    float tempB2;
+    float tempFrac;
+    int tempB2Int;
+    uint8_t negativeFlag = 0;
     
     if (b2 & 0x8000){
         b2 ^= 0xFFFF;
         b2 -= 1;
-        negative_flag = 1;
+        negativeFlag = 1;
     }
     
-    temp_b2_int = b2 & 0x4000;
-    temp_b2_int = temp_b2_int >> b2_frac_bits;
+    tempB2Int = b2 & 0x4000;
+    tempB2Int = tempB2Int >> b2FracBits;
     
-    temp_b2 = temp_b2_int * 1.0;
-    temp_frac = (b2 & b2_frac_mask) * (1.0/(1<<b2_frac_bits));
-    temp_b2 = temp_b2 + temp_frac;
+    tempB2 = tempB2Int * 1.0;
+    tempFrac = (b2 & b2FracMask) * (1.0/(1<<b2FracBits));
+    tempB2 = tempB2 + tempFrac;
     
-    if(negative_flag) temp_b2 = -temp_b2;
+    if(negativeFlag) tempB2 = -tempB2;
     
-    return temp_b2;
+    return tempB2;
 }
 
 
-float get_c12(uint16_t c12){
-    float temp_c12;
-    float temp_frac;
-    uint8_t negative_flag = 0;
+float getC12(uint16_t c12){
+    float tempC12;
+    float tempFrac;
+    uint8_t negativeFlag = 0;
     
     c12 = c12 >> 2;
     
     if (c12 & 0x2000){
         c12 ^= 0xFFFF;
         c12 -= 1;
-        negative_flag = 1;
+        negativeFlag = 1;
     }
     
-    temp_c12 = 0.000000000;
-    temp_frac = (c12 & c12_frac_mask) * (1.0/(1<<c12_frac_bits));
-    temp_c12 = temp_c12 + temp_frac;
+    tempC12 = 0.000000000;
+    tempFrac = (c12 & c12FracMask) * (1.0/(1<<c12FracBits));
+    tempC12 = tempC12 + tempFrac;
     
-    if(negative_flag) temp_c12 = -temp_c12;
+    if(negativeFlag) tempC12 = -tempC12;
     
-    return temp_c12;
+    return tempC12;
 }
 
 float MPL115A1::getPressure(){
@@ -115,7 +124,7 @@
     uint16_t padc = 0;
     uint16_t tadc = 0;
 
-    float a0_f, b1_f, b2_f, c12_f;
+    float a0F, b1F, b2F, c12F;
     cs = 0;
     spi.write(0x88);        // MSB a0
     a0 = spi.write(0x00);   
@@ -175,21 +184,21 @@
     spi.write(0x00);
     cs = 1;
     
-    a0_f  = get_a0(a0);
-    b1_f  = get_b1(b1);
-    b2_f  = get_b2(b2);
-    c12_f = get_c12(c12);
+    a0F  = getA0(a0);
+    b1F  = getB1(b1);
+    b2F  = getB2(b2);
+    c12F = getC12(c12);
     
     /*            
-    float c12x2 = c12_f * tadc;
-    float a1_f = b1_f + c12x2;
-    float a1x1 = a1_f * padc;
-    float y1 = a0_f + a1x1;
-    float a2x2 = b2_f * tadc;
+    float c12x2 = c12F * tadc;
+    float a1F = b1F + c12x2;
+    float a1x1 = a1F * padc;
+    float y1 = a0F + a1x1;
+    float a2x2 = b2F * tadc;
     pcomp = y1 + a2x2;
     */
 
-    pcomp = a0_f + (b1_f + c12_f * tadc) * padc + b2_f * tadc;
+    pcomp = a0F + (b1F + c12F * tadc) * padc + b2F * tadc;
     pressure = pcomp * ((115-50)/(1023.0)) + 52;    // Was + 50
     pressure *= 10;     // Calculate in hPa
     return pressure;