更新 AGS10-TVOC库

boards/default_src/micropython/origin/build/lib/ags10.py

@@ -0,0 +1,96 @@
+"""
+AGS10
+
+Micropython library for the AGS10(TVOC)
+=======================================================
+@dahanzimin From the Mixly Team
+"""
+import time
+from micropython import const
+
+_AGS10_ADC         = const(0x00)
+_AGS10_CAL         = const(0x01)
+_AGS10_RES         = const(0x20)
+_AGS10_ADD         = const(0x21)
+
+class AGS10:
+    def __init__(self, i2c_bus, address=0x1A, delay=1000):
+        self._i2c = i2c_bus
+        self._addr = address
+        self._voc = None
+        self._delay = delay
+        self._star = 0
+
+    def _crc8(self, buf, is_byte=False):
+        '''Perform CRC check on the data'''
+        crc = 0xff
+        for byte in buf:
+            crc ^= byte
+            for _ in range(8):
+                if crc & 0x80:
+                    crc = (crc << 1) ^ 0x31
+                else:
+                    crc = crc << 1
+        return  crc.to_bytes(1, 'little') if is_byte else crc & 0xff
+
+    def _wreg(self, reg, buf):
+        '''Write memory address'''
+        self._i2c.writeto_mem(self._addr, reg, buf)
+        time.sleep_ms(20)
+
+    def _rreg(self, reg, nbytes=5):
+        '''Read memory address'''
+        _buf = self._i2c.readfrom_mem(self._addr, reg, nbytes)
+        time.sleep_ms(20)
+        return _buf[:4] if self._crc8(_buf[:4]) == _buf[4] else None
+
+    def address(self, addr=None):
+        _scan = self._i2c.scan()
+        if addr is None:
+            if self._addr in _scan:
+                return self._addr
+            elif len(_scan) == 1:
+                self._addr = _scan[0]
+                return self._addr
+            else:
+                return None
+        else:
+            if self.address():
+                if 8<= addr <=119:
+                    _buf = bytes([addr, (~ addr) & 0xff] * 2)
+                    self._wreg(_AGS10_ADD, _buf + self._crc8(_buf, True))
+                    if addr in self._i2c.scan():
+                        self._addr = addr
+                        return True
+                else:
+                    raise ValueError("Not within the valid range of 8-119")
+
+    def calibration(self, zero=1):
+        '''0: Factory restoration 1:Sensor resistance'''
+        _buf = b'\x00\x0c'
+        _buf += b'\x00\x00' if zero else b'\xff\xff' 
+        self._wreg(_AGS10_ADD,  _buf + self._crc8(_buf, True))
+
+    @property
+    def getdata(self):
+        if time.ticks_diff(time.ticks_ms(), self._star) >= self._delay: 
+            self._star = time.ticks_ms() 
+            _buf = self._rreg(_AGS10_ADC)
+            if (_buf[0] & 0x01) == 0:
+                self._voc = int.from_bytes(_buf[1:4], 'big')
+        return self._voc / 1000
+
+    def read(self, hcho_mw=30.033 , co2_mv=0.853, co2_base=400):
+        '''unit ppm'''
+        self.getdata
+        _voc = self._voc / 1000 #ppm
+        return round( _voc, 2), round( _voc / hcho_mw, 2), co2_base + round( _voc / co2_mv, 2)
+
+    def tvoc(self):
+        return self.read()[0]
+
+    def hcho(self, tvoc_mw=30.053):
+        return self.read(hcho_mw=hcho_mw)[1]
+
+    def eco2(self, co2_mv=0.853):
+        return self.read(co2_mv=co2_mv)[2]