drivers/lps22h: Add LPS22HB/HH pressure sensor driver.

drivers/lps22h/lps22h.py

@@ -0,0 +1,117 @@
+"""
+The MIT License (MIT)
+
+Copyright (c) 2016-2019 shaoziyang <shaoziyang@micropython.org.cn>
+Copyright (c) 2022 Ibrahim Abdelkader <iabdalkader@openmv.io>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+LPS22HB/HH pressure sensor driver for MicroPython.
+
+Example usage:
+
+import time
+from lps22h import LPS22H
+from machine import Pin, I2C
+
+bus = I2C(1, scl=Pin(15), sda=Pin(14))
+lps = LPS22H(bus, oneshot=False)
+
+while (True):
+    print("Pressure: %.2f hPa Temperature: %.2f C"%(lps.pressure(), lps.temperature()))
+    time.sleep_ms(10)
+"""
+import machine
+
+_LPS22_CTRL_REG1 = const(0x10)
+_LPS22_CTRL_REG2 = const(0x11)
+_LPS22_STATUS = const(0x27)
+_LPS22_TEMP_OUT_L = const(0x2B)
+_LPS22_PRESS_OUT_XL = const(0x28)
+_LPS22_PRESS_OUT_L = const(0x29)
+
+
+class LPS22H:
+    def __init__(self, i2c, address=0x5C, oneshot=False):
+        self.i2c = i2c
+        self.addr = address
+        self.oneshot = oneshot
+        self.buf = bytearray(1)
+
+        if hasattr(machine, "idle"):
+            self._go_idle = machine.idle()
+        else:
+            import time
+
+            self._go_idle = lambda: time.sleep_ms(1)
+
+        # ODR=1 EN_LPFP=1 BDU=1
+        self._write_reg(_LPS22_CTRL_REG1, 0x1A)
+        self.set_oneshot_mode(self.oneshot)
+
+    def _int16(self, d):
+        return d if d < 0x8000 else d - 0x10000
+
+    def _write_reg(self, reg, dat):
+        self.buf[0] = dat
+        self.i2c.writeto_mem(self.addr, reg, self.buf)
+
+    def _read_reg(self, reg, width=8):
+        self.i2c.readfrom_mem_into(self.addr, reg, self.buf)
+        val = self.buf[0]
+        if width == 16:
+            val |= self._read_reg(reg + 1) << 8
+        return val
+
+    def _tigger_oneshot(self, b):
+        if self.oneshot:
+            self._write_reg(_LPS22_CTRL_REG2, self._read_reg(_LPS22_CTRL_REG2) | 0x01)
+            self._read_reg(0x28 + b * 2)
+            while True:
+                if self._read_reg(_LPS22_STATUS) & b:
+                    return
+                self._go_idle()
+
+    def set_oneshot_mode(self, oneshot):
+        self._read_reg(_LPS22_CTRL_REG1)
+        self.oneshot = oneshot
+        if oneshot:
+            self.buf[0] &= 0x0F
+        else:
+            self.buf[0] |= 0x10
+        self._write_reg(_LPS22_CTRL_REG1, self.buf[0])
+
+    def pressure(self):
+        if self.oneshot:
+            self._tigger_oneshot(1)
+        return (
+            self._read_reg(_LPS22_PRESS_OUT_XL) + self._read_reg(_LPS22_PRESS_OUT_L, 16) * 256
+        ) / 4096
+
+    def temperature(self):
+        if self.oneshot:
+            self._tigger_oneshot(2)
+        return self._int16(self._read_reg(_LPS22_TEMP_OUT_L, 16)) / 100
+
+    def altitude(self):
+        return (
+            (((1013.25 / self.pressure()) ** (1 / 5.257)) - 1.0)
+            * (self.temperature() + 273.15)
+            / 0.0065
+        )