# Change sensitivity/resolution of usb mouse? [Solved]

## ppurka

I am in a fix right now. The wireless usb mouse I have (Logitech v550 nano) has too high sensitivity and I believe that it has 800dpi resolution.

With google searches, I have learnt that Option "Resolution" 800 should suffice and that by default X assumes the resolution to be 90. However, this does not work with the usb mouse. Additionally, changes to mouse acceleration and threshold in X also does not seem to have any effect, or if it does, then the effect is negligible. 

Other google searches have led to the possibility to tune a different parameter /sys/module/usbhid/parameters/mousepoll, which apparently changes the frequency with which the usbhid module polls the mouse; the default being 100Hz. Is this parameter in any way related to the resolution? I did "echo 2 > /sys/module/usbhid/parameters/mousepoll" but even this had no visible effect on the mouse sensitivity (even after unpluggin and replugging the mouse). 

Is there some other method I can adopt to change the resolution as seen by X? At present I am completely out of ideas.

The following is my xorg.conf 

```
Section "ServerLayout"

    Identifier     "Layout0"

    Screen      0  "Screen0" 0 0

    InputDevice    "Touchpad" "AlwaysCore"

    InputDevice    "Keyboard0" "CoreKeyboard"

    InputDevice    "Mouse0" "CorePointer"

    InputDevice     "LogitechMouse" "SendCoreEvents"

    Option         "BlankTime" "5"

    Option         "StandbyTime" "7"

    Option         "SuspendTime" "9"

    Option         "OffTime" "12"

EndSection

Section "Files"

    RgbPath         "/usr/lib/X11/rgb"

    FontPath    "/usr/share/fonts/misc:unscaled"

    FontPath    "/usr/share/fonts/dejavu"

    FontPath    "/usr/share/fonts/75dpi:unscaled"

    FontPath    "/usr/share/fonts/100dpi:unscaled"

    FontPath    "/usr/local/share/fonts"

EndSection

Section "Module"

    Load           "dbe"

    Load           "extmod"

    SubSection     "extmod"

        Option         "omit xfree86-dga"   # don't initialise the DGA extension

    EndSubSection

    Load           "type1"

    Load           "freetype"

    Load           "glx"

EndSection

Section "InputDevice"

    # generated from default

    Identifier     "Keyboard0"

    Driver         "kbd"

    Option         "XkbModel"   "thinkpad"

EndSection

Section "InputDevice"

    # generated from data in "/etc/conf.d/gpm"

    Identifier     "Mouse0"

    Driver         "mouse"

    Option         "Protocol" "ExplorerPS/2"

    Option         "Device" "/dev/input/mice"

    Option         "Buttons" "7"

    Option         "ZAxisMapping" "4 5"

    Option         "EmulateWheel" "yes"

    Option         "EmulateWheelButton" "2"

    Option         "XAxisMapping" "6 7"

    Option         "YAxisMapping" "4 5"

EndSection

Section "InputDevice"

    # Logitech mouse

    Identifier      "LogitechMouse"

    Driver          "evdev"

    Option          "Phys"          "usb-0000:00:1d.0-2/input0"

    Option          "HWHEELRelativeAxisButtons"     "7 6"

EndSection

Section "InputDevice"

    Identifier     "TouchPad"

    Driver         "synaptics"

    Option         "SendCoreEvents" 

    Option         "Device" "/dev/psaux"

    Option         "Protocol" "auto-dev"

    Option         "RightEdge" "5300"

    Option         "TopEdge" "1700"

    Option         "BottomEdge" "4200"

    Option         "FingerLow" "15"

    Option         "FingerHigh" "40"

    Option         "MaxTapTime" "180"

    Option         "MaxTapMove" "180"

    Option         "VertScrollDelta" "100"

    Option         "MinSpeed" "0.09"

    Option         "MaxSpeed" "0.18"

    Option         "AccelFactor" "0.0015"

    Option         "SHMConfig" "1"

    #Disable middle click and right click

    Option         "TapButton1" "1"

    Option         "TapButton2" "0"

    Option         "TapButton3" "0"

    #Enable circular scrolling

    Option         "CircularScrolling" "1"

    Option         "CircScrollTrigger" "2" #Top Right Corner

EndSection

Section "Monitor"

    Identifier     "Monitor0"

    VendorName     "Unknown"

    ModelName      "Unknown"

EndSection

Section "Device"

    Identifier     "Device0"

    Driver         "nvidia"

    VendorName     "NVIDIA Corporation"

EndSection

Section "Screen"

    Identifier  "Screen0"

    Device      "Device0"

    Monitor     "Monitor0"

    DefaultDepth 24

    Option      "NoLogo"            "true"

    Option      "DPI"               "100x100"

EndSection

Section "Extensions"

    Option         "Composite" "Enable"

EndSection
```

Thanks

----------

## Malvineous

I use xset to adjust my sensitivity:

```
xset m 5/2
```

Maybe that would help?  I've never had any troubles specifying extremely high or low values.

Alternatively if lomoco supports your mouse you might be able to lower the DPI in the mouse itself.

----------

## ppurka

 *Malvineous wrote:*   

> I use xset to adjust my sensitivity:
> 
> ```
> xset m 5/2
> ```
> ...

 Like I mentioned above, changing acceleration or threshold in X does not have any visible effect. I have even tried setting it to 1/1 (since I want to decrease sensitivity.

Yes, I forgot to mention in my post: I had tried lomoco but this mouse is not in its database,- it just spits out that it is an unsupported mouse.

```
~> lomoco -p c526 -8

005.006: 046d:c526 Unsupported Logitech device: USB Receiver
```

----------

## Malvineous

Setting it to 1/1 wouldn't decrease the sensitivity, it would just set it to "normal".  Try 1/10 or 1/100.  If this doesn't work then you're not using X11 devices to control the pointer (e.g. you're using something like synergy to control the pointer from another PC.)

----------

## ppurka

Many thanks. That seems to work, and it does decrease the sensitivity.  :Very Happy: 

----------

## ppurka

Just a follow-up post:

I am quite positive that I had tried fractional acceleration parameters before, using the kde's mouse dialog. It goes up (down?) to 0.1x in the mouse dialog of kde,- that would be equivalent to xset m 1/10. It had no effect on the usb mouse sensitivity.

What has changed recently is that I upgraded xorg-server to 1.5.3-r3 yesterday. Along with that a lot of things just worked, for example the usb mouse has horizontal scroll when we rock the scroll wheel from side to side. This never worked out of the box with the previous xorg-server-1.3. With 1.5.3, it just worked with absolutely no hal/xorg configuration required from my side. Additionally, the fractional mouse acceleration settings has started to work too for the usb mouse.

Thanks to Malvineous's second post, I tried the setting again, and this time it worked!

----------

## Malvineous

Glad to hear the problem is fixed!  Recent X11 versions include a hotplug mouse driver, which has different button assignments to the old evdev driver (or the standard mouse driver, which only supported five buttons.)  Unfortunately I couldn't use it as my mouse has 12 buttons and these aren't all supported by the hotplug driver, so I had to go back to evdev and use xset to remap the buttons to get horizontal scroll working.

----------

