diff --git a/cfg/sim6502.cfg b/cfg/sim6502.cfg
index c768ab4a3..39c33581c 100644
--- a/cfg/sim6502.cfg
+++ b/cfg/sim6502.cfg
@@ -3,7 +3,7 @@ SYMBOLS {
     __STACKSIZE__: type = weak, value = $0800; # 2k stack
 }
 MEMORY {
-    ZP:     file = "",               start = $0000, size = $001B;
+    ZP:     file = "",               start = $0000, size = $0100;
     HEADER: file = %O,               start = $0000, size = $000C;
     MAIN:   file = %O, define = yes, start = $0200, size = $FDF0 - __STACKSIZE__;
 }
diff --git a/cfg/sim65c02.cfg b/cfg/sim65c02.cfg
index c768ab4a3..39c33581c 100644
--- a/cfg/sim65c02.cfg
+++ b/cfg/sim65c02.cfg
@@ -3,7 +3,7 @@ SYMBOLS {
     __STACKSIZE__: type = weak, value = $0800; # 2k stack
 }
 MEMORY {
-    ZP:     file = "",               start = $0000, size = $001B;
+    ZP:     file = "",               start = $0000, size = $0100;
     HEADER: file = %O,               start = $0000, size = $000C;
     MAIN:   file = %O, define = yes, start = $0200, size = $FDF0 - __STACKSIZE__;
 }