updated readme

keyboards/launchpad/readme.md

@@ -27,6 +27,16 @@ See [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools)
 
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+![Underglow](https://i.imgur.com/3zFIOmu.jpg)
+
+SpaceCat now provides an underglow add-on kit. Please refer to the picture above for wiring.
+
+Make example for this keyboard (after setting up your build environment):
+
+    make launchpad/rev1:default_rgb
+
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+
 Due to PCB tolerance issues outside of our control, the snap-apart legs included on the PCB may need extra padding to prevent a small amount of wobbling once placed properly. We have included small, clear, and semi-permanent "glue dots" in each order (PCB Only -and- Full Kit) to help with this. You may also use plastic wrap, tape, Elmer's glue, hot glue, rubber cement, etc. We advise against using anything more "permanent" in case you wish to make changes to your Launch Pad in the future. It is also best to attach legs after all of your soldering and building is finished, to get the most accurate feel for your Launch Pad.
 
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