diff --git a/src/bus/GamePak.zig b/src/bus/GamePak.zig
index b6c65b2..fe7461d 100644
--- a/src/bus/GamePak.zig
+++ b/src/bus/GamePak.zig
@@ -113,14 +113,14 @@ pub fn write(self: *Self, comptime T: type, word_count: u16, address: u32, value
 
     switch (T) {
         u32 => switch (address) {
-            0x0800_00C4 => log.err("Wrote {} 0x{X:} to I/O Port Data and Direction", .{ T, value }),
-            0x0800_00C6 => log.err("Wrote {} 0x{X:} to I/O Port Direction and Control", .{ T, value }),
+            0x0800_00C4 => log.debug("Wrote {} 0x{X:} to I/O Port Data and Direction", .{ T, value }),
+            0x0800_00C6 => log.debug("Wrote {} 0x{X:} to I/O Port Direction and Control", .{ T, value }),
             else => {},
         },
         u16 => switch (address) {
-            0x0800_00C4 => log.err("Wrote {} 0x{X:} to I/O Port Data", .{ T, value }),
-            0x0800_00C6 => log.err("Wrote {} 0x{X:} to I/O Port Direction", .{ T, value }),
-            0x0800_00C8 => log.err("Wrote {} 0x{X:} to I/O Port Control", .{ T, value }),
+            0x0800_00C4 => log.debug("Wrote {} 0x{X:} to I/O Port Data", .{ T, value }),
+            0x0800_00C6 => log.debug("Wrote {} 0x{X:} to I/O Port Direction", .{ T, value }),
+            0x0800_00C8 => log.debug("Wrote {} 0x{X:} to I/O Port Control", .{ T, value }),
             else => {},
         },
         u8 => log.debug("Wrote {} 0x{X:} to 0x{X:0>8}, Ignored.", .{ T, value, address }),
diff --git a/src/util.zig b/src/util.zig
index 975b667..fdb127f 100644
--- a/src/util.zig
+++ b/src/util.zig
@@ -102,13 +102,13 @@ pub const FilePaths = struct {
 };
 
 pub fn readUndefined(log: anytype, comptime format: []const u8, args: anytype) u8 {
-    log.debug(format, args);
+    log.warn(format, args);
     if (builtin.mode == .Debug) std.debug.panic("TODO: Implement I/O Register", .{});
 
     return 0;
 }
 
 pub fn writeUndefined(log: anytype, comptime format: []const u8, args: anytype) void {
-    log.debug(format, args);
+    log.warn(format, args);
     if (builtin.mode == .Debug) std.debug.panic("TODO: Implement I/O Register", .{});
 }