diff --git a/CHANGELOG b/CHANGELOG
index a12610b..c2a6ee7 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,4 @@
+2024-05-23: do not install system files when building/installing as user (#27) [9664f5f]
 2024-05-23: new tool upload_firmware_6022.py (upload to different VID:PID) [c85792d]
 2024-05-06: make scopevis.py example program really useful [ea05828]
 2024-05-03: upversion 2.10.8; update examples and doc [ac44d00]
diff --git a/README.md b/README.md
index 4a6401b..40323f9 100644
--- a/README.md
+++ b/README.md
@@ -49,9 +49,10 @@ This means:
 
 - download this repo (as `https://github.com/Ho-Ro/Hantek6022API/archive/refs/heads/main.zip`)
 - or execute `git clone https://github.com/Ho-Ro/Hantek6022API.git`
+- to enable user access to the device copy (as root) the file `udev/60-hantek6022api.rules`
+into `/etc/udev/rules.d`
 - go to `examples`
-- try e.g. `python3 get_serial_number.py`.
-
+- try e.g. `python3 get_serial_number.py`
 
 ## Developer Info
 
diff --git a/examples/README.md b/examples/README.md
index 530b354..3315232 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -91,9 +91,9 @@ usage: upload_6022_firmware_from_hex.py HEXFILE
 Uploads firmware from intel hex file to device
 
 ### `upload_6022_firmware.py`
-Uploads standard firmware to device - deprecated, will be replaced by ´upload_firmware_6022.py´
+Uploads standard firmware to device - deprecated, will be replaced by `upload_firmware_6022.py`
 
-### ´upload_firmware_6022.py´
+### `upload_firmware_6022.py`
 ```
 usage: upload_firmware_6022.py [-h] [-V VID] [-P PID] [--be | --bl]
 
@@ -101,12 +101,28 @@ Upload firmware to Hantek6022 devices with different VID:PID
 
 options:
   -h, --help         show this help message and exit
-  -V VID, --VID VID
-  -P PID, --PID PID
-  --be, --6022be
-  --bl, --6022bl
+  -V VID, --VID VID  set vendor id (hex)
+  -P PID, --PID PID  set product id (hex)
+  --be, --6022be     use DSO-6022BE firmware
+  --bl, --6022bl     use DSO-6022BL firmware
+```
+
+This tool can be used to upload the firmware to devices with
+[damaged EEPROM content](https://github.com/Ho-Ro/Hantek6022API/discussions/28).
+These devices enumerate as Cypress development kit with VID:PID 04b4:8613.
+
+```
+$ lsusb | grep Cypress
+Bus 002 Device 021: ID 04b4:8613 Cypress Semiconductor Corp. CY7C68013 EZ-USB FX2 USB 2.0 Development Kit
+
+$ ./upload_firmware_6022.py --VID 04b4 --PID 8613 --6022be
+upload DSO-6022BE firmware
+FW version 0x210
+Serial number CF81BA1F3532
+
+$ lsusb | grep Hantek
+Bus 002 Device 022: ID 04b5:6022 ROHM LSI Systems USA, LLC Hantek DSO-6022BE
 ```
 
 ### `reset_eeprom_6022.py`
 **Warning:** this program will delete all calibration values from EEPROM - use with care!
-
diff --git a/examples/upload_firmware_6022.py b/examples/upload_firmware_6022.py
index 76e3b42..6e5c9e2 100755
--- a/examples/upload_firmware_6022.py
+++ b/examples/upload_firmware_6022.py
@@ -14,14 +14,14 @@
 ap = argparse.ArgumentParser(
     prog='upload_firmware_6022.py',
     description='Upload firmware to Hantek6022 devices with different VID:PID' )
-ap.add_argument( '-V', '--VID', type = lambda x: int(x,16), default = 0 )
-ap.add_argument( '-P', '--PID', type = lambda x: int(x,16), default = 0 )
+ap.add_argument( '-V', '--VID', type = lambda x: int(x,16), default = 0, help = 'set vendor id (hex)' )
+ap.add_argument( '-P', '--PID', type = lambda x: int(x,16), default = 0, help = 'set product id (hex)' )
 fw = ap.add_mutually_exclusive_group()
-fw.add_argument( '--be', '--6022be', action = 'store_true' )
-fw.add_argument( '--bl', '--6022bl', action = 'store_true' )
+fw.add_argument( '--be', '--6022be', action = 'store_true', help = 'use DSO-6022BE firmware' )
+fw.add_argument( '--bl', '--6022bl', action = 'store_true', help = 'use DSO-6022BL firmware' )
 
 options = ap.parse_args()
-print( options.VID, options.PID )
+
 if not options.VID and not options.PID:
     scope = Oscilloscope()
 elif options.VID and options.PID and ( options.be or options.bl ):
@@ -30,17 +30,24 @@
     print( '--VID and --PID and one of --be or --bl must be provided')
     sys.exit()
 
-scope.setup()
+if not scope.setup():
+    print( 'scope setup error - no device?' )
+    sys.exit( -1 )
+
 if not scope.open_handle():
-    print( 'No device' )
+    print( 'scope open error - no device?' )
     sys.exit( -1 )
 
 if options.be:
+    print( 'upload DSO-6022BE firmware' )
     scope.flash_firmware( dso6022be_firmware )
 elif options.bl:
+    print( 'upload DSO-6022BL firmware' )
     scope.flash_firmware( dso6022bl_firmware )
 else:
+    print( 'upload default firmware' )
     scope.flash_firmware()
 
 print( "FW version", hex( scope.get_fw_version() ) )
+print( "Serial number", scope.get_serial_number_string() )
 scope.close_handle()