initial version hx711 librairie for lopy

.gitignore

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+
+*.e4q
+
+scale.e4p
+
+0.1
+
+.eric6project/scale.e6t

hx711.py

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+from machine import Pin
+
+class HX711:
+    def __init__(self, dout, pd_sck, gain=128):
+
+        self.pSCK = Pin(pd_sck , mode=Pin.OUT)
+        self.pOUT = Pin(dout, mode=Pin.IN, pull=Pin.PULL_DOWN)
+
+        self.GAIN = 0
+        self.OFFSET = 0
+        self.SCALE = 1
+        self.lastVal = 0
+        self.allTrue = False
+
+        self.set_gain(gain);
+
+
+    def createBoolList(size=8):
+        ret = []
+        for i in range(8):
+            ret.append(False)
+        return ret
+
+    def is_ready(self):
+        return self.pOUT() == 0
+
+    def set_gain(self, gain):
+        if gain is 128:
+            self.GAIN = 1
+        elif gain is 64:
+            self.GAIN = 3
+        elif gain is 32:
+            self.GAIN = 2
+
+        self.pSCK.value(False)
+        self.read()
+        print('Gain setted')
+
+    def read(self):
+
+        dataBits = [self.createBoolList(), self.createBoolList(), self.createBoolList()]
+        while not self.is_ready():
+            pass
+
+        for j in range(2, -1, -1):
+            for i in range(7, -1, -1):
+                self.pSCK.value(True)
+                dataBits[j][i] = self.pOUT()
+                self.pSCK.value(False)
+
+
+        #set channel and gain factor for next reading
+        for i in range(self.GAIN):
+            self.pSCK.value(True)
+            self.pSCK.value(False)
+
+
+        #check for all 1
+        if all(item == True for item in dataBits[0]):
+            print('all true')
+            self.allTrue=True
+            return self.lastVal
+
+        self.allTrue=False
+
+
+        readbits = ""
+        for j in range(2, -1, -1):
+            for i in range(7, -1, -1):
+                if dataBits[j][i] == True:
+                    readbits= readbits +'1'
+                else:
+                    readbits= readbits+'0'
+
+        self.lastVal = int(readbits, 2)
+
+        return self.lastVal
+
+
+
+    def read_average(self, times=3):
+        sum = 0
+        effectiveTimes = 0
+        readed = 0
+        for i in range(times):
+            readed = self.read()
+            if self.allTrue == False:
+                sum += readed
+                effectiveTimes+=1
+
+        if effectiveTimes == 0:
+            return 0
+        return sum / effectiveTimes
+
+    def get_value(self, times=3):
+        return self.read_average(times) - self.OFFSET
+
+    def get_units(self, times=3):
+        return self.get_value(times) / self.SCALE
+
+    def tare(self, times=15):
+        sum = self.read_average(times)
+        self.set_offset(sum)
+
+    def set_scale(self, scale):
+        self.SCALE = scale
+
+    def set_offset(self, offset):
+        self.OFFSET = offset
+
+    def power_down(self):
+        self.pSCK.value(False)
+        self.pSCK.value(True)
+
+
+    def power_up(self):
+        self.pSCK.value(False)
+

scale.py

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+from hx711 import HX711
+hx = HX711('G9', 'G10')
+hx.set_scale(48.36)
+hx.tare()
+val = hx.get_units(5)
+print(val)