From 7d32b770f284bebe388629b62623262245b6b185 Mon Sep 17 00:00:00 2001 From: iabdalkader Date: Tue, 5 Jul 2022 22:14:48 +0200 Subject: [PATCH] drivers/lps22h: Add LPS22HB/HH pressure sensor driver. --- drivers/lps22h/lps22h.py | 117 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 drivers/lps22h/lps22h.py diff --git a/drivers/lps22h/lps22h.py b/drivers/lps22h/lps22h.py new file mode 100644 index 000000000..8d90b2917 --- /dev/null +++ b/drivers/lps22h/lps22h.py @@ -0,0 +1,117 @@ +""" +The MIT License (MIT) + +Copyright (c) 2016-2019 shaoziyang +Copyright (c) 2022 Ibrahim Abdelkader + +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 + )