mirror bakside png

src/pressure.py

@@ -0,0 +1,64 @@
+#!/usr/bin/python3
+# encoding: UTF-8
+
+import sys, time
+
+debug = 0
+
+def calibrate(Word, D):
+
+    C=[0]*7
+    C[1] = Word[1] >> 1
+    C[2] = ((Word[3] & 0x3f)<<6) | (Word[4] & 0x3f) 
+    C[3] = Word[4]>>6
+    C[4] = Word[3]>>6
+    C[5] = ((Word[1] & 1)<<10) | (Word[2]>>6)
+    C[6] = Word[2] & 0x3f
+
+    if debug:
+       sys.stdout.write("""
+    C1 = %d
+    C2 = %d
+    C3 = %d
+    C4 = %d
+    C5 = %d
+    C6 = %d
+    """ % tuple(C[1:7]))
+    
+    UT1 = 8*C[5]+20224
+    dT = D[2] - UT1
+    TEMP = 200 + dT*(C[6]+50)/1024
+    
+    if debug:
+       print(f"{D[3]=} {UT1=} {dT=} {TEMP=:.2f} °C", file=sys.stderr)
+    
+    OFF = C[2]*4 + ((C[4]-512)*dT)/4096
+    SENS = C[1] + (C[3]*dT)/1024 + 24576
+    X = (SENS * (D[1]-7168))/16384 - OFF
+    P = X*10/32 + 2500
+    
+    if debug:
+       print(f"{D[1]=} {OFF=:.2f} {SENS=:.2f} {P=:.2f}", file=sys.stderr)
+
+    return (TEMP,P)
+
+
+def main():
+    data = [0]*7
+    import fileinput
+    for l in fileinput.input(errors='backslashreplace'):
+        if l[0]=='T':
+            t = int(l.split()[1],0)
+            print(f"{time.time():.1f} {t} {time.strftime('%FT%TZ', time.gmtime(t))}")
+        if l[0]=='W':
+            data[1:5] = [int(ll,16) for ll in l.split()[1:]]
+        elif l[0]=='D':
+            data[5:] = [int(ll,16) for ll in l.split()[1:]]
+            if data[1]:
+                T,p = calibrate(data, data[4:])
+                print(f"{T/10:.2f} °C, {p/10:.2f} mbar")
+        elif l[0] in "PV":
+            print(l.strip())
+
+if __name__=="__main__":
+    main()