Fixed pressure unit conversion error

titonbarua · Jan 1, 2025 · d6aa943 · d6aa943
1 parent 7e98700
commit d6aa943
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Showing 4 changed files with 5 additions and 7 deletions.
diff --git a/ms5837/bar02.py b/ms5837/bar02.py
@@ -53,7 +53,7 @@ def _calc_pressure_temp(self, raw_p, raw_t):
         TEMP2 = (TEMP - Ti) * 0.01  # degree-C
         P2 = (
             (((D1 * SENS2) >> 21) - OFF2) >> 15
-        ) * 0.01  # mBar = KPa
+        ) * 0.001  # 1 KPa = 10 mBar
 
         # Units: (KPa, degree-C)
         return P2, TEMP2
diff --git a/ms5837/bar30.py b/ms5837/bar30.py
@@ -63,7 +63,7 @@ def _calc_pressure_temp(self, raw_p, raw_t):
         TEMP2 = (TEMP - Ti) * 0.01  # °C
         P2 = (
             (((D1 * SENS2) >> 21) - OFF2) >> 13
-        ) * 0.1  # mBar = KPa
+        ) * 0.01  # 1 KPa = 10 mBar
 
         # Units: (KPa, degree-C)
         return P2, TEMP2
diff --git a/ms5837/depth.py b/ms5837/depth.py
@@ -31,7 +31,7 @@ def __init__(
         self._p_ref = float(ref_pressure)
 
     def set_ref_pressure(self, n_measurements=10):
-        """Set reference pressure from measurements by the sensor."""
+        """Set reference pressure in KPa from measurements by the sensor."""
         s = 0.0
         for _ in range(n_measurements):
             p_abs, _ = self._ms5837.read()
@@ -48,7 +48,7 @@ def _calc_depth_m(self, abs_pressure):
 
         # Liquid pressure, P = h x rho x g
         #               => h = P / (rho x g)
-        h = (p_rel * 100.0) / self._g_x_rho
+        h = (p_rel * 1000.0) / self._g_x_rho
 
         # Unit: m
         return h

diff --git a/tests/rp2040_tests.py b/tests/rp2040_tests.py
@@ -67,10 +67,8 @@ def _create_sensor(type_, osr):
     return (i2c_obj, sensor)
 
 
-# _OSR_RATES = [256, 512, 1024, 2048, 4096]
 _BAR30_OSR_RATES = [256, 512, 1024, 2048, 4096]
 _BAR02_OSR_RATES = [256, 512, 1024, 2048, 4096, 8192]
-# [256, 512, 1024, 2048, 4096]
 
 # Number of measurements per OSR for timing.
 _N = 100
@@ -257,7 +255,7 @@ def print_depth(sensor_type, water_density=1000, interval_sec=1.0):
         while True:
             try:
                 d_m = depth_estimator.read_depth()
-                print("Depth: {:.2f} mm".format(d_m * 1000))
+                print("Depth: {:+.3f} cm".format(d_m * 100))
                 time.sleep(interval_sec)
             except KeyboardInterrupt:
                 break