diff --git a/src/ide/views/debugviews.ts b/src/ide/views/debugviews.ts
index 8fec2c1f..256e82ab 100644
--- a/src/ide/views/debugviews.ts
+++ b/src/ide/views/debugviews.ts
@@ -704,7 +704,7 @@ export class ScanlineIOView extends ProbeViewBaseBase {
           var sym = platform.debugSymbols.addr2symbol[addr];
           if (sym) line[-1] = sym;
           break;
-        case ProbeFlags.MEM_WRITE:
+        //case ProbeFlags.MEM_WRITE:
         case ProbeFlags.IO_READ:
         case ProbeFlags.IO_WRITE:
         case ProbeFlags.VRAM_READ:
diff --git a/src/platform/vcs.ts b/src/platform/vcs.ts
index cd42dbf2..961c523d 100644
--- a/src/platform/vcs.ts
+++ b/src/platform/vcs.ts
@@ -385,13 +385,17 @@ class VCSPlatform extends BasePlatform {
       bus.oldRead = bus.read;
       bus.read = function(a) {
         var v = this.oldRead(a);
-        probe.logRead(a,v);
+        if (a < 0x80) probe.logIORead(a,v);
+        else if (a > 0x280 && a < 0x300) probe.logIORead(a,v);
+        else probe.logRead(a,v);
         return v;
       }
       bus.oldWrite = bus.write;
       bus.write = function(a,v) {
         this.oldWrite(a,v);
-        probe.logWrite(a,v);
+        if (a < 0x80) probe.logIOWrite(a,v);
+        else if (a > 0x280 && a < 0x300) probe.logIOWrite(a,v);
+        else probe.logWrite(a,v);
       }
     }
     return rec;