diff --git a/src/processor/memory.rs b/src/processor/memory.rs
index bf98c94..14251de 100644
--- a/src/processor/memory.rs
+++ b/src/processor/memory.rs
@@ -224,13 +224,15 @@ impl Memory {
                     }
                 }
                 0xFF04 => self.io[addr_l] = 0,
-                0xFF07 => {
-                    self.masked_io(addr_l, data, 0b111);
-                }
-                0xFF0F => {
-                    self.masked_io(addr_l, data, 0b11111);
-                }
-                0xFF11 | 0xFF14 | 0xFF16 | 0xFF19 | 0xFF1E | 0xFF23 | 0xFF26 => {
+                0xFF07 => self.masked_io(addr_l, data, 0b111),
+                0xFF0F => self.masked_io(addr_l, data, 0b11111),
+                0xFF10 => self.masked_io(addr_l, data, 0b01111111),
+                0xFF1A => self.masked_io(addr_l, data, 0b10000000),
+                0xFF1C => self.masked_io(addr_l, data, 0b1100000),
+                0xFF20 => self.masked_io(addr_l, data, 0b111111),
+                0xFF23 => self.io[addr_l] = (self.io[addr_l] & 0b10111111) | (data & 0b01000000),
+                0xFF26 => self.io[addr_l] = (self.io[addr_l] & 0b1111111) | (data & 0b10000000),
+                0xFF11 | 0xFF14 | 0xFF16 | 0xFF19 | 0xFF1E => {
                     // sound
                     self.io[addr_l] = data;
                 }
@@ -242,7 +244,16 @@ impl Memory {
                     // cgb only
                     self.io[addr_l] = data;
                 }
-                0xFF44 | 0xFF76 | 0xFF77 => {
+                0xFF03
+                | 0xFF08..0xFF0F
+                | 0xFF15
+                | 0xFF1F
+                | 0xFF27
+                | 0xFF28
+                | 0xFF29
+                | 0xFF44
+                | 0xFF76
+                | 0xFF77 => {
                     // read-only addresses
                     println!("BANNED write: {data:#X} to {address:#X}");
                 }