First commit

device.py

@@ -0,0 +1,121 @@
+"""
+NMEA2000-Gerät
+- auf dem Bus erkannte Geräte
+- für das eigene Gerät steht initUid() zur Verfügung
+
+"""
+
+import time
+import struct
+from . import lookup
+
+class Device():
+
+    def __init__(self, address):
+        # WIP: Felder können sich noch ändern!
+        self.address = address       # Kann sich zur Laufzeit ändern
+        self.lastseen = time.time()
+        self.lastpinfo = None        # Wann letztes Mal Productinfo erhalten?
+        self.lastcinfo = None        # Wann letztes Mal Configurationinfo erhalten?
+        self.has_cinfo = True        # Weitere Abfragen können verhindert werden
+
+        # Device info
+        self.NAME = 0                # Wird über getNAME (address claim) gefüllt, 64bit Integer
+        self.uniqueid = None         # Z.B. aus der Geräteseriennummer abgeleitet
+        self.manufacturercode = 2046 # Open Boat Projects
+        self.instance = 0            # default 0
+        self.instlower = 0           # 3bit, ISO ECU Instance
+        self.instupper = 0           # 5bit, ISO Function Instance
+        self.sysinstance = 0         # used with bridged networks, default 0
+        self.industrygroup = None
+        self.devicefunction = None
+        self.deviceclass = None
+
+        # Product info
+        self.product = None             # Product name
+        self.productcode = None         # Product code
+        self.serial = None
+        self.modelvers = None 		# Hardware Version
+        self.softvers = None            # Current Software Version
+        self.n2kvers = None             # NMEA2000 Network Message Database Version
+        self.certlevel = None           # NMEA2000 Certification Level
+        self.loadequiv = None           # NMEA2000 LEN
+
+        # Configuration info
+        self.instdesc1 = None
+        self.instdesc2 = None
+        self.manufinfo = None 
+
+        # Additional data
+        self.customname = None          # User defined device name
+
+    def _ISOtime(self, epoch):
+        if not epoch:
+            return "n/a"
+        return time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(epoch))
+
+    def initUid(self):
+        # Initialize unique id from raspi cpu id and return 21bit value
+        with open("/sys/firmware/devicetree/base/serial-number", "r") as f:
+            hexid = f.read().rstrip('\x00')
+        return int(hexid, 16) & 0x001FFFFF # 21bit mask
+
+    def getNAME(self):
+        """
+        NAME is unique on bus
+        Returns bytearray and sets integer NAME for later easy and fast access
+        """
+        data = bytearray()
+        data.extend(struct.pack('<I', (self.uniqueid & 0x001fffff) | (self.manufacturercode << 21)))
+        data.append((self.instlower & 0x07) | ((self.instupper & 0x1f) << 3))
+        data.append(self.devicefunction)
+        data.append((self.deviceclass & 0x7f) << 1)
+        data.append(0x80 | ((self.industrygroup & 0x07) << 4) | (self.sysinstance & 0x0f))
+        self.NAME = struct.unpack_from('<Q', data, 0)[0]
+        return data
+
+    def __str__(self):
+        out =  f"Device: {self.address} : '{self.product}'\n"
+        out +=  "  NAME: {} ({})\n".format(self.getNAME(), self.NAME)
+        out +=  "  last seen: {}\n".format(self._ISOtime(self.lastseen))
+        out +=  "  Device info\n"
+        out += f"    Unique ID: {self.uniqueid}\n"
+        out += f"    Instance: {self.instance} ({self.instupper}/{self.instlower})\n"
+        out += f"    System instance: {self.sysinstance}\n"
+        try:
+            devfnname = lookup.devicefunction[self.deviceclass][self.devicefunction]
+        except KeyError:
+            devfnname = "*key error*"
+        out += f"    Device function: {devfnname} ({self.devicefunction})\n"
+        try:
+            devclassname = lookup.deviceclass[self.deviceclass]
+        except KeyError:
+            devclassname = "*key error*"
+        out += f"    Device class: {devclassname} ({self.deviceclass})\n"
+        try:
+            igrpname = lookup.industrygroup[self.industrygroup]
+        except KeyError:
+            igrpname = "*key error*"
+        out += f"    Industry group: {igrpname} ({self.industrygroup})\n"
+        try:
+            manufname = lookup.manufacturer[self.manufacturercode]
+        except KeyError:
+            manufname = "*key error*"
+        out += f"    Manufacturer code: {manufname} ({self.manufacturercode})\n"
+        out +=  "  Product info at {}\n".format(self._ISOtime(self.lastpinfo))
+        out += f"    Product Code: {self.productcode}\n"
+        out += f"    Product: {self.product}\n"
+        out += f"    Serial: {self.serial}\n"
+        out += f"    Model Version: {self.modelvers}\n"
+        out += f"    Software Version: {self.softvers}\n"
+        out += f"    NMEA2000 Version: {self.n2kvers}\n"
+        out += f"    Cert-Level: {lookup.certlevel[self.certlevel]} ({self.certlevel})\n"
+        out += f"    LEN: {self.loadequiv}\n"
+        out +=  "  Configuration info at {}\n".format(self._ISOtime(self.lastcinfo))
+        if self.has_cinfo:
+            out += f"    Installation description 1: {self.instdesc1}\n"
+            out += f"    Installation description 2: {self.instdesc2}\n"
+            out += f"    Manufacturer info: {self.manufinfo}\n"
+        else:
+            out += "    not available\n"
+        return out