Wrote CAN Bus data visualizer

tools/canmonitor/monitor.py

@@ -0,0 +1,114 @@
+from binascii import unhexlify
+import tkinter.ttk as ttk
+import tkinter as tk
+import serial
+
+APPNAME = "CAN Bus Spy"
+BLOCK_WIDTH = 8
+BLOCK_HEIGHT = 32
+
+class MainWindow:
+    def __init__(self, parent):
+        self.parent = parent
+        self.create_widgets()
+        self.create_layout()
+
+    def create_widgets(self):
+        self.frame = ttk.Frame(self.parent)
+
+        self.viewText = tk.Text(self.frame, height=BLOCK_HEIGHT, width=7 + (BLOCK_WIDTH * 4))
+        self.viewText.tag_configure("ascii", foreground="green")
+        self.viewText.tag_configure("error", foreground="red")
+        self.viewText.tag_configure("hexspace", foreground="navy")
+        self.viewText.tag_configure("graybg", background="lightgray")
+
+        self.viewText.tag_configure("id", foreground="blue")
+
+    def create_layout(self):
+        self.viewText.grid(row=1, column=0, columnspan=6, sticky=tk.NSEW)
+        self.frame.grid(row=0, column=0, sticky=tk.NSEW)
+
+    def show_data(self, table):
+        self.viewText.delete("1.0", "end")
+
+        for id, data in sorted(table.items()):
+            # Print the frame id
+            self.viewText.insert("end", "{:04d}".format(id), ("id"))
+            self.viewText.insert("end", "  ")
+
+            # Print the frame as hex
+            for byte in data:
+                tags = ()
+                if 0x20 < byte < 0x7F:
+                    tags = ("ascii")
+                self.viewText.insert("end", "{:02X} ".format(byte), tags)
+
+            # Insert some padding
+            self.viewText.insert("end", " " * (BLOCK_WIDTH - len(data)) * 3)
+
+            self.viewText.insert("end", " ")
+
+            # Print the frame as ascii
+            for char in data.decode("ascii", errors="replace"):
+                tags = ()
+
+                if char in "\u2028\u2029\t\n\r\v\f\uFFFD":
+                    char = "."
+                    tags = ("graybg" if char == "\uFFFD" else "error",)
+                elif 0x20 < ord(char) < 0x7F:
+                    tags = ("ascii",)
+                elif not 0x20 <= ord(char) <= 0xFFFF: # Tcl/Tk limit
+                    char = "?"
+                    tags = ("error",)
+
+                self.viewText.insert("end", char, tags)
+
+            self.viewText.insert("end", "\n")
+
+    def quit(self, event=None):
+        self.parent.destroy()
+
+class InvalidFrame(Exception):
+    pass
+
+def parse(line):
+    # FRAME ID=234 LEN=3 AB:EE:69
+    frame = line.split(':', maxsplit=3)
+
+    try:
+        frame_id = int(frame[1][3:])
+        frame_length = int(frame[2][4:])
+
+        hex_data = frame[3].replace(':', '')
+
+        data = unhexlify(hex_data)
+
+    except (IndexError, ValueError) as exc:
+        raise InvalidFrame("Invalid frame {}".format(line)) from exc
+
+    if len(data) != frame_length:
+        raise InvalidFrame("Wrong frame length or invalid data: {}".format(line))
+
+    return frame_id, data
+
+ser = serial.Serial("/dev/ttyUSB0", 115200)
+table = {}
+
+def task():
+    if ser.in_waiting:
+        line = str(ser.readline().rstrip(), "ascii")
+        print(line)
+        id, data = parse(line)
+        table[id] = data
+
+    window.show_data(table)
+    app.after(10, task)
+
+
+app = tk.Tk()
+app.title(APPNAME)
+window = MainWindow(app)
+app.protocol("WM_DELETE_WINDOW", window.quit)
+app.resizable(width=False, height=False)
+app.after(0, task)
+app.mainloop()

tools/canmonitor/test.txt

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+Hello world, this is a test