Catch PipeError and print a friendly debug message

Author: yuvadm

md380_tool.py

@@ -112,12 +112,12 @@ def read_framebuf_line(self, y):
                   chr(0) +    # x1 (x1,y1) = tile's upper left corner
                   chr(y) +    # y1
                   chr(159) +  # x2 (x2,y2) = tile's lower right corner
-                  chr(y)      # y2 
+                  chr(y)      # y2
                   )
            self._device.ctrl_transfer(0x21, Request.DNLOAD, 1, 0, cmdstr)
            self.get_status()  # this changes state
            status = self.get_status()  # this gets the status
-           # read 5-byte header (echo of cmdstr) followed by 
+           # read 5-byte header (echo of cmdstr) followed by
            # 160 pixels per line * 3 bytes per pixel (BLUE,GREEN,RED):
            rd_result = self.upload(1, 160*3+5, 0);
            if rd_result[4] == y:  # y2 ok -> got the expected response
@@ -282,8 +282,8 @@ def custom(self, cmd):
         status = self.get_status()  # this gets the status
 
     def reboot_to_bootloader(self):
-        """Reboot into the bootloader with a DFU command. 
-        This will erase (part of) the firmware from flash, 
+        """Reboot into the bootloader with a DFU command.
+        This will erase (part of) the firmware from flash,
         so you must reprogram the firmware afterwards if you'd like a working radio.
         """
         cmd = 0x86  # reboot_to_bootloader
@@ -427,8 +427,8 @@ def screenshot(dfu, filename="screenshot.bmp"):
     with open(filename, 'wb') as f:
       # Write a simple, hard-coded bitmap file header
       #  (14 byte "file header" + 40 byte "info block" + 3*160*128 byte "data",
-      #   total size = 0x0000F036 bytes. Here written in little endian format: 
-      f.write( "BM" + chr(0x36)+chr(0xF0)+chr(0x00)+chr(0x00) 
+      #   total size = 0x0000F036 bytes. Here written in little endian format:
+      f.write( "BM" + chr(0x36)+chr(0xF0)+chr(0x00)+chr(0x00)
                     + chr(0x00)+chr(0x00)+chr(0x00)+chr(0x00)
                     + chr( 54 )+chr(0x00)+chr(0x00)+chr(0x00) )
       # Next: Write the "bitmap info header". Keep it simple, use 40 bytes.
@@ -446,7 +446,7 @@ def screenshot(dfu, filename="screenshot.bmp"):
       # Write image data with 160 pixels per line, 3 bytes per pixel.
       # For a start, just dump the pixels to the file unmodified.
       y = 127; # bmp files begin with the 'bottom line' (y=127)
-      while y>=0:  
+      while y>=0:
         buf = dfu.read_framebuf_line(y)
         f.write(buf)
         y = y-1;
@@ -751,7 +751,7 @@ def usage():
     md380-tool readword <0xcafebabe>
 Dump 1kB from arbitrary address
     md380-tool dump <filename.bin> <address>
-Dump calibration data 
+Dump calibration data
     md380-tool calibration
 Reboot into the bootloader (erases application, you _must_ reflash firmware afterwards):
     md380-tool reboot_to_bootloader
@@ -884,6 +884,11 @@ def main():
     except RuntimeError as e:
         print(e.args[0])
         exit(1)
+    except usb.core.USBError as ue:
+        print(ue)
+        if ue[0] == 32:
+            print('Make sure the device is already flashed with custom firmware and NOT in DFU mode')
+        exit(1)
     except Exception as e:
         print(e)
         # print(dfu.get_status())