HP203B

Author: qqqlab

src/madflight/bar/BarGizmoHP203B.h

@@ -3,6 +3,27 @@
 #include "bar.h"
 #include "../hal/MF_I2C.h"
 
+/*
+OSR  T[ms]  ADC_CVT
+ 128   4.1 0b01010100
+ 256   8.2 0b01010000
+ 512  16.4 0b01001100
+1024  32.8 0b01001000
+2048  65.6 0b01000100
+4096 131.1 0b01000000 
+*/
+
+#define HP203B_SOFT_RST 0x06 //SOFT_RST soft reset
+#define HP203B_ANA_CAL 0x28 //ANA_CAL Re-calibrate the Internal analog Blocks
+#define HP203B_ADC_CVT_256 0b01010000 //start conversion: ADC_CVT = 010, 100 OSR=256 (8.2ms), 00 press+temp
+#define HP203B_READ_PT 0x10 //READ_PT pressure [Pa] + temp [0.01*C]
+#define HP203B_READ_AT 0x11 //READ_AT altitude [0.01*m] + temp [0.01*C]
+
+#define HP203B_INT_SRC 0x8D
+#define HP203B_INT_SRC_DEV_RDY (1<<6) //only access device when 1
+#define HP203B_INT_SRC_PA_RDY (1<<5) //press/alt conversion ready
+
+
 class BarGizmoHP203B: public BarGizmo {
 private:
   MF_I2CDevice *dev;
@@ -12,35 +33,30 @@ class BarGizmoHP203B: public BarGizmo {
     if(i2c_adr == 0) i2c_adr = 0x76; // fixed: 0x76 or 0x77
     this->dev = new MF_I2CDevice(i2c, i2c_adr);
 
-    dev->writeReg(0x06, nullptr, 0); //SOFT_RST soft reset
-    dev->writeReg(0x28, nullptr, 0); //ANA_CAL Re-calibrate the Internal analog Blocks
-    dev->writeReg(0b01010000, nullptr, 0); //start conversion: ADC_CVT = 010, 100 OSR=256 (8.2ms), 00 press+temp
+    dev->writeReg(HP203B_SOFT_RST, nullptr, 0); //SOFT_RST soft reset
+    delay(1); //FIXME: should check HP203B_INT_SRC_DEV_RDY
+    dev->writeReg(HP203B_ANA_CAL, nullptr, 0); //ANA_CAL Re-calibrate the Internal analog Blocks
+    delay(1); //FIXME: should check HP203B_INT_SRC_DEV_RDY
+    dev->writeReg(HP203B_ADC_CVT_256, nullptr, 0); //start conversion: ADC_CVT = 010, 100 OSR=256 (8.2ms), 00 press+temp
   }
 
   ~BarGizmoHP203B() {
     delete dev;
   }
 
-
-
-/*
-OSR  T[ms]  ADC_CVT
- 128   4.1 0b01010100
- 256   8.2 0b01010000
- 512  16.4 0b01001100
-1024  32.8 0b01001000
-2048  65.6 0b01000100
-4096 131.1 0b01000000 
-*/
   bool update(float *press, float *temp) override {
+    //only read device when dev_rdy and pa_rdy
+    //FIXME: put timeout on waiting for pa_rdy
+    const uint8_t mask = HP203B_INT_SRC_DEV_RDY | HP203B_INT_SRC_DEV_RDY;
+    if( dev->readReg(HP203B_INT_SRC) & mask != mask) return false;
+   
     uint8_t d[6];
-    dev->readReg(0x10, d, 6); //READ_PT pressure [Pa] + temp [0.01*C]
-    //dev->readReg(0x11, d, 6); //READ_AT altitude [0.01*m] + temp [0.01*C]
-    dev->writeReg(0b01010000, nullptr, 0); //start conversion: ADC_CVT = 010, 100 OSR=256 (8.2ms), 00 press+temp
+    dev->readReg(HP203B_READ_PT, d, 6); //READ_PT pressure [Pa] + temp [0.01*C]
+    dev->writeReg(HP203B_ADC_CVT_256, nullptr, 0); //start conversion: ADC_CVT = 010, 100 OSR=256 (8.2ms), 00 press+temp
 
     int32_t t = ((d[0] << 16) | (d[1] << 8) | d[2]) & 0x000fffff; //20 bit big-endian signed
     if(t & 0x00080000) t |= 0xfff00000; //20bit sign expansion
-    uint32_t p = ((d[3] << 16) | (d[4] << 8) | d[5]) & 0x000fffff; //20 bit big-endian unsigned
+    int32_t p = ((d[3] << 16) | (d[4] << 8) | d[5]) & 0x000fffff; //20 bit big-endian unsigned
 
     *temp = t * 0.01; //temperature in [C]
     *press = p; //pressure in [Pa]