X to phone keypad mapping reference

X_KEYPAD_MAPPING.md

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+# X11 Keypad Mapping for different models
+
+On all models, digits 0 to 9 are mapped as normal ASCII keysyms 0x30 to 0x39, and the D-pad keys are mapped as `Left`/`Up`/`Right`/`Down`.
+
+Here are the special key mappings.
+
+## Nokia 8110 4G (`nokia-argon`)
+
+- `*`: `KP_Multiply`
+- `#`: `KP_Divide`
+- Soft Left: `Menu`
+- Soft Right: `XF86Back`
+- Soft Center: `Return`
+- Call: `XF86Phone`
+- End/Backspace: `BackSpace`
+- Power: `XF86PowerOff`
+
+## Nokia 2720 Flip (`nokia-beatles`)
+
+TBD
+
+## Nokia 800 Tough (`nokia-coconut`)
+
+TBD
+
+## Nokia 8000 4G (`nokia-sparkler`)
+
+TBD
+