Worked on the analysis

Samples/400-552-259/1-invalid/400-552-259.txt

@@ -0,0 +1,9 @@
+
+
+Decoded stream for 400-552-259:
+-------------------------------
+
+0xaa, 0xaa, 0xaa, 0xaa, 0x5b, 0xfd, 0xdd, 0x79, 0xc5, 0xf1, 0xe2, 0xbb, 0x1e, 0x2d, 0xf6, 0x60, 0x81, 0x19, 0x03, 0x70, 0x60, 0xb9, 0x96, 0x3f, 0xdb, 0xf7
+
+
+

crc16/TI-crc16.py

@@ -0,0 +1,36 @@
+import sys
+
+def culCalcCRC(crcData, crcReg):
+    CRC_POLY = 0x8005
+
+    for i in xrange(0, 8):
+        if ((((crcReg & 0x8000) >> 8) ^ (crcData & 0x80)) & 0xFFFF):
+            crcReg = (((crcReg << 1) & 0xFFFF) ^ CRC_POLY) & 0xFFFF
+        else:
+            crcReg = (crcReg << 1) & 0xFFFF
+        crcData = (crcData << 1) & 0xFF
+
+    return crcReg
+
+def crc16(txtBuffer, expectedChksum):
+    CRC_INIT = 0xFFFF
+    checksum = CRC_INIT
+
+    hexarray = bytearray.fromhex(txtBuffer)
+    for i in hexarray:
+        checksum = culCalcCRC(i, checksum)
+
+    if checksum == int(expectedChksum, 16):
+        print "CRC OK"
+        return True
+    else:
+        print "CRC Fail. Expected=" + expectedChksum + " Calculated=" + str(hex(checksum))
+        return False
+
+#
+# Main
+#
+payload = "11431d070ea270e904cfbf737e47cfa334e0"
+expectedCrc = "1204"
+success = crc16(payload, expectedCrc)
+print "Match" + success