diff --git a/chiptune_debug/TODO b/chiptune_debug/TODO
new file mode 100644
index 00000000..1ee2d957
--- /dev/null
+++ b/chiptune_debug/TODO
@@ -0,0 +1,4 @@
++ Write only the C channel
++ Write the same value to the C channel
++ Run at 25Hz
++ not use ABS addressing