# Expansion options using WebControl's GPIO functionality **URL:** \ **Category:** General Discussion\ **Created:** [May 14, 2022, 6:02pm UTC](https://forums.maslowcnc.com/t/expansion-options-using-webcontrols-gpio-functionality/18015 "2022-05-14T18:02:04Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![macgeeknz](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@macgeeknz](https://forums.maslowcnc.com/u/macgeeknz)\ **Post date:** [May 14, 2022, 6:02pm UTC](https://forums.maslowcnc.com/t/expansion-options-using-webcontrols-gpio-functionality/18015/1 "2022-05-14T18:02:04Z")
Wow! I just spotted that WebControl has a bunch of different events you can tie to GPIO states, eg buttons for startup / shutdown in addition to e-stop, play/pause and return to centre! That’s super-cool. Has anyone used this to build an on-machine control panel or control a ‘traffic light’ indicator before? I think that could be a really useful addition to my machine. I wonder if it would be possible to add other features, eg a 4-button ‘50mm step’ arrow jogger… (yes I know, mobile phone and pendant http access - but I love physical buttons!) Does anyone know what MCP means in ‘WebMCP Running’? ---
**Author:** ![dlang](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/dlang/32/859_2.png) [@dlang](https://forums.maslowcnc.com/u/dlang)\ **Post date:** [May 14, 2022, 6:26pm UTC](https://forums.maslowcnc.com/t/expansion-options-using-webcontrols-gpio-functionality/18015/2 "2022-05-14T18:26:37Z")
> Does anyone know what MCP means in ‘WebMCP Running’? early versions (docker based) had a ‘master control program’ that then ran webcontrol, I’m not sure if that’s still used. David Lang ---
**Author:** ![Orob](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/orob/32/16344_2.png) [@Orob](https://forums.maslowcnc.com/u/Orob)\ **Post date:** [May 15, 2022, 12:18am UTC](https://forums.maslowcnc.com/t/expansion-options-using-webcontrols-gpio-functionality/18015/3 "2022-05-15T00:18:48Z")
I did the button thing and was toying around with offering laser cut panels with labels for custom control bittons