diff --git a/src/ButtonMapping.ld b/src/ButtonMapping.ld
new file mode 100644
index 0000000..8953e55
--- /dev/null
+++ b/src/ButtonMapping.ld
@@ -0,0 +1,4 @@
+$$ = 0;
+
+/* 0x80011c18 in GMSJ01 */
+$C2$.postPADClamp = 0x40 + JUTGamePad.read;
diff --git a/src/ButtonMapping.s b/src/ButtonMapping.s
new file mode 100644
index 0000000..948afa0
--- /dev/null
+++ b/src/ButtonMapping.s
@@ -0,0 +1,16 @@
+.set rBtn, 11
+
+.postPADClamp:
+## read button input
+  lhz rBtn, 0(r31)
+
+.map.Z.to.DR:
+  cmplwi rBtn, 0x10
+  bne .map.Z.to.DR.done
+  li rBtn, 0x2
+  sth rBtn, 0(r31)
+.map.Z.to.DR.done:
+
+.done:
+## orig
+  li r29, 0