diff --git a/BizHawk.Emulation/Computers/Commodore64/C64.MotherboardInterface.cs b/BizHawk.Emulation/Computers/Commodore64/C64.MotherboardInterface.cs
index 31ff65c49f..46613f9d6e 100644
--- a/BizHawk.Emulation/Computers/Commodore64/C64.MotherboardInterface.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/C64.MotherboardInterface.cs
@@ -74,7 +74,10 @@ namespace BizHawk.Emulation.Computers.Commodore64
 
         byte Cpu_ReadPort()
         {
-            return 0xFF;
+            byte data = 0x1F;
+            if (!cassPort.Sense)
+                data &= 0xEF;
+            return data;
         }
 
         bool Cpu_ReadRDY()
diff --git a/BizHawk.Emulation/Computers/Commodore64/MOS/MOS6510.cs b/BizHawk.Emulation/Computers/Commodore64/MOS/MOS6510.cs
index dc4cac9c9e..ce170f1349 100644
--- a/BizHawk.Emulation/Computers/Commodore64/MOS/MOS6510.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/MOS/MOS6510.cs
@@ -70,7 +70,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
             // configure data port defaults
             port = new LatchedPort();
             port.Direction = 0x00;
-            port.Latch = 0x1F;
+            port.Latch = 0xFF;
 
             // NMI is high on startup (todo: verify)
             pinNMILast = true;
@@ -152,7 +152,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
         {
             get
             {
-                return port.ReadOutput();
+                return port.ReadInput(ReadPort());
             }
             set
             {