From 8bc4ee036d0d005d5eb450a540a496ccaef33183 Mon Sep 17 00:00:00 2001
From: Andreas Gattringer <andreas.gattringer@univie.ac.at>
Date: Wed, 6 Dec 2023 08:51:57 +0100
Subject: [PATCH] added lps28dfw support
---
.../sensors/lps28dfw/__init__.py | 205 ++++++++++++++++++
1 file changed, 205 insertions(+)
create mode 100644 umnp/microcontroller/sensors/lps28dfw/__init__.py
diff --git a/umnp/microcontroller/sensors/lps28dfw/__init__.py b/umnp/microcontroller/sensors/lps28dfw/__init__.py
new file mode 100644
index 0000000..31d0b79
--- /dev/null
+++ b/umnp/microcontroller/sensors/lps28dfw/__init__.py
@@ -0,0 +1,205 @@
+import asyncio
+import struct
+import time
+
+try:
+ from machine import I2C
+except ImportError:
+ from umnp.microcontroller.umock.machine import I2C
+
+LPS28DFW_DEFAULT_ADDRESS = 0x5C
+LPS28DFW_READ = 0xB9
+LPS28DFW_WRITE = 0xB8
+
+LPS28DFW_CTRL_REG1 = 0x10
+LPS28DFW_CTRL_REG2 = 0x11
+LPS28DFW_CTRL_REG3 = 0x12
+LPS28DFW_CTRL_REG4 = 0x13
+
+LPS28DFW_WHO_AM_I = 0x0F
+
+LPS28DFW_TEMP_OUT_H = 0x2B
+LPS28DFW_TEMP_OUT_L = 0x2C
+
+
+LPS28DFW_PRESS_OUT_H = 0x2A
+LPS28DFW_PRESS_OUT_L = 0x29
+LPS28DFW_PRESS_OUT_XL = 0x28
+LPS28DFW_STATUS = 0x27
+
+VALID_FREQUENCIES_HZ = [0, 1, 4, 10, 25, 50, 75, 100, 200]
+VALID_AVERAGING = [4, 8, 16, 32, 64, 128, 512]
+
+
+class LPS28DFW:
+ def __init__(self, i2c: I2C, i2c_address=LPS28DFW_DEFAULT_ADDRESS):
+ self._i2c = i2c
+ self._i2c_address = i2c_address
+ self._initialised = False
+ self._nan = float("NAN")
+
+ devices = self._i2c.scan()
+
+ if self._i2c_address not in devices:
+ raise RuntimeError("LPS28DFW: Device not found")
+
+ if self.initialise():
+ self._initialised = True
+ else:
+ raise RuntimeError("Could not initialise device")
+
+ self._divisions = self._get_divisions()
+
+ def initialise(self) -> bool:
+ self.set_frequency(25)
+ self.set_averaging(512)
+ return True
+
+ def read_address(self, address, n_bytes):
+ return self._i2c.readfrom_mem(self._i2c_address, address, n_bytes)
+
+ def write_address(self, address, buffer) -> None:
+ self._i2c.writeto_mem(self._i2c_address, address, buffer)
+
+ def _get_divisions(self) -> int:
+ reg2 = self.read_address_to_int(LPS28DFW_CTRL_REG2, 1)
+ mode = self.get_bit(reg2, 6)
+ if mode == 0:
+ return 4096
+ else:
+ return 2048
+
+ async def one_shot(self):
+ reg1 = self.read_address_to_int(LPS28DFW_CTRL_REG1, 1)
+ reg1 = self.unset_bit(reg1, 3)
+ reg1 = self.unset_bit(reg1, 4)
+ reg1 = self.unset_bit(reg1, 5)
+ reg1 = self.unset_bit(reg1, 6)
+ self.write_single_byte(LPS28DFW_CTRL_REG1, reg1)
+
+ reg2 = self.read_address_to_int(LPS28DFW_CTRL_REG2, 1)
+ reg2 = self.set_bit(reg2, 0)
+ self.write_single_byte(LPS28DFW_CTRL_REG2, reg2)
+ await asyncio.sleep(0.01)
+ data = self.read_address_to_int(LPS28DFW_PRESS_OUT_XL, 3)
+ pressure = data / self._get_divisions()
+ return pressure
+
+ def set_frequency(self, frequency):
+ if frequency not in VALID_FREQUENCIES_HZ:
+ raise RuntimeError(f"Invalid frequency {frequency}")
+ idx = VALID_FREQUENCIES_HZ.index(frequency)
+ reg1 = self.read_address_to_int(LPS28DFW_CTRL_REG1, 1)
+ reg1 &= 0b111
+ reg1 = (idx << 3) + reg1
+ self.write_single_byte(LPS28DFW_CTRL_REG1, reg1)
+
+ def set_averaging(self, count):
+ if count not in VALID_AVERAGING:
+ raise RuntimeError(f"Invalid averaging count {count}")
+ idx = VALID_AVERAGING.index(count)
+ reg1 = self.read_address_to_int(LPS28DFW_CTRL_REG1, 1)
+ reg1 &= 0b11111000
+ reg1 += idx
+ self.write_single_byte(LPS28DFW_CTRL_REG1, reg1)
+
+ def debug(self):
+ whoami = self.read_address(LPS28DFW_WHO_AM_I, 1)
+ print("Who am I", whoami)
+
+ reg1 = self.read_address(LPS28DFW_CTRL_REG1, 1)
+ print("Register 1", reg1)
+
+ reg2 = self.read_address(LPS28DFW_CTRL_REG2, 1)
+ print("Register 2:", reg2)
+
+ reg3 = self.read_address(LPS28DFW_CTRL_REG3, 1)
+ print("Register 3", reg3)
+
+ def write_single_byte(self, register, value):
+ buffer = bytearray(1)
+ buffer[0] = value
+ self.write_address(register, buffer)
+
+ @staticmethod
+ def set_bit(value: int, bit: int) -> int:
+ mask = 1 << bit
+ value |= mask
+ return value
+
+ @staticmethod
+ def unset_bit(value: int, bit: int) -> int:
+ mask = 1 << bit
+ value &= ~mask
+
+ return value
+
+ @staticmethod
+ def get_bit(value: int, bit: int) -> int:
+ mask = 1 << bit
+ return value & mask
+
+ def read_address_to_int(self, address, n_bytes):
+ data = self.read_address(address, n_bytes)
+ if n_bytes == 1:
+ return int.from_bytes(data, "little")
+ elif n_bytes == 2:
+ return struct.unpack("<h", data)[0]
+ elif n_bytes == 3:
+ value = struct.unpack("<I", data + "\0")[0]
+ if value & 0x800000:
+ return value - 0x1000000
+ else:
+ return value
+ raise RuntimeError(f"can't convert {n_bytes} byte integers")
+
+ def boot(self):
+ # fresh the content of the internal registers stored in the non-volatile memory block
+ reg2 = self.read_address_to_int(LPS28DFW_CTRL_REG2, 1)
+ reg2 = self.set_bit(reg2, 7)
+
+ self.write_single_byte(LPS28DFW_CTRL_REG2, reg2)
+ time.sleep(0.1)
+ self._divisions = self._get_divisions()
+
+ def software_reset(self):
+ # resets the volatile registers to the default value
+ reg2 = self.read_address_to_int(LPS28DFW_CTRL_REG2, 1)
+ reg2 = self.set_bit(reg2, 2)
+ self.write_single_byte(LPS28DFW_CTRL_REG2, reg2)
+ time.sleep(0.1)
+ self._divisions = self._get_divisions()
+
+ def pressure_status(self):
+ status = self.read_address_to_int(LPS28DFW_STATUS, 1)
+ avail_mask = 1 << 0
+ overrun_mask = 1 << 4
+ return status & avail_mask == avail_mask, status & overrun_mask == overrun_mask
+
+ def temperature_status(self):
+ status = self.read_address_to_int(LPS28DFW_STATUS, 1)
+ avail_mask = 1 << 1
+ overrun_mask = 1 << 5
+ return status & avail_mask == avail_mask, status & overrun_mask == overrun_mask
+
+ async def pressure(self):
+ while True:
+ avail, overrun = self.pressure_status()
+ if avail:
+ break
+ await asyncio.sleep(0.01)
+
+ pressure = self.read_address_to_int(LPS28DFW_PRESS_OUT_XL, 3)
+ pressure = pressure / self._divisions
+ return pressure
+
+ async def temperature(self):
+ while True:
+ avail, overrun = self.temperature_status()
+ if avail:
+ break
+ await asyncio.sleep(0.01)
+
+ temperature = self.read_address_to_int(LPS28DFW_TEMP_OUT_L, 2)
+ temperature = temperature / 100
+ return temperature
--
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