Can I suggest an improvement to the documentation?

[agent4125]

I was playing around with advancemame, trying to get both a trackball and 2 spinners working on the same control panel on my retropie bartop.

I followed this guide here from the official docs: https://retropie.org.uk/docs/Spinners,-Trackballs,-Lightguns,-and-other-Mouse-Devices/

This worked, but on reboots there was no consistency that the mouse indexes stayed the same, so sometimes my spinner and trackballs would work, sometimes they wouldn't. Especially if I plugged in a keyboard for configuration, or other USB devices (extra game pads, etc).

This bit in particular in advmame.rc (or the 1.4 version of the file): -

device_raw_mousedev[0] /dev/input/mouse0
device_raw_mousedev[1] /dev/input/mouse1
device_raw_mousedev[2] /dev/input/mouse2
device_raw_mousedev[3] /dev/input/mouse3

...some boots, /dev/input/mouse0 was trackball, and /dev/input/mouse2 was spinner.
...some boots, /dev/input/mouse2 was trackball, and /dev/input/mouse1 was spinner.
etc.
etc.

I fixed this by using the IDs of the trackball and spinner devices instead of the indexes.

For example, you can find the ids by typing: -

ls -l /dev/input/by-id

lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-1241_1111-event-mouse -> ../event4
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-1241_1111-mouse -> ../mouse2
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-GGG_TurboTwist_Spinner-event-mouse -> ../event0
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-GGG_TurboTwist_Spinner-mouse -> ../mouse0
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-Ultimarc_IPAC_2_Ultimarc_IPAC_2_9-event-if02 -> ../event3
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-Ultimarc_IPAC_2_Ultimarc_IPAC_2_9-event-kbd -> ../event1
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-Ultimarc_IPAC_2_Ultimarc_IPAC_2_9-if01-event-mouse -> ../event2
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-Ultimarc_IPAC_2_Ultimarc_IPAC_2_9-if01-mouse -> ../mouse1

For me, the lines I was interested in were the following two: -

lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-1241_1111-mouse -> ../mouse2
lrwxrwxrwx 1 root root 9 Apr 23 15:30 usb-GGG_TurboTwist_Spinner-mouse -> ../mouse0

The first is my trackball, the second my spinner (2 spinners share 1 mouse port on different axes).

So I solved this by updating the advmame.rc file as follows: -

device_raw_mousedev[0] /dev/input/by-id/usb-GGG_TurboTwist_Spinner-mouse
device_raw_mousedev[1] /dev/input/mouse1
device_raw_mousedev[2] /dev/input/by_id/usb-1241_1111-mouse
device_raw_mousedev[3] /dev/input/mouse3

Then when setting up dials/paddles/sticks/trackballs in the input section of the .rc file I can consistently use the indexes 0 and 2.

Just in case others might find this helpful (it would have saved me a LOT of time and frustration if it was on the page). Perhaps the docs could be updated with this information to help others?

Cheers

[mitu]

That's a good suggestion. I added some notes on persistent device paths.