diff --git a/compiler/src/prog8/compiler/target/c64/codegen/ForLoopsAsmGen.kt b/compiler/src/prog8/compiler/target/c64/codegen/ForLoopsAsmGen.kt
index 2f0ce3c6f..31f7dbd2c 100644
--- a/compiler/src/prog8/compiler/target/c64/codegen/ForLoopsAsmGen.kt
+++ b/compiler/src/prog8/compiler/target/c64/codegen/ForLoopsAsmGen.kt
@@ -279,8 +279,8 @@ $endLabel       inx""")
                     sta  $loopLabel+1
                     sty  $loopLabel+2
 $loopLabel          lda  ${65535.toHex()}       ; modified
-                    beq  $endLabel""")
-                asmgen.out("  sta  ${asmgen.asmIdentifierName(stmt.loopVar)}")
+                    beq  $endLabel
+                    sta  ${asmgen.asmIdentifierName(stmt.loopVar)}""")
                 asmgen.translate(stmt.body)
                 asmgen.out("""
                     inc  $loopLabel+1
@@ -290,60 +290,64 @@ $loopLabel          lda  ${65535.toHex()}       ; modified
 $endLabel""")
             }
             DataType.ARRAY_UB, DataType.ARRAY_B -> {
-                // TODO: optimize loop code when the length of the array is 255 or less instead of 256
                 val length = decl.arraysize!!.size()!!
-                val counterLabel = asmgen.makeLabel("for_counter")      // todo allocate dynamically, zero page preferred if len >= 16
-                val modifiedLabel = asmgen.makeLabel("for_modified")
+                val indexVar = asmgen.makeLabel("for_index")      // TODO allocate dynamically, zero page preferred if length >= 16
                 asmgen.out("""
-                    lda  #<$iterableName
-                    ldy  #>$iterableName
-                    sta  $modifiedLabel+1
-                    sty  $modifiedLabel+2
                     ldy  #0
-$loopLabel          sty  $counterLabel
-$modifiedLabel      lda  ${65535.toHex()},y       ; modified""")
-                asmgen.out("  sta  ${asmgen.asmIdentifierName(stmt.loopVar)}")
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  ${asmgen.asmIdentifierName(stmt.loopVar)}""")
                 asmgen.translate(stmt.body)
+                if(length<=255) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 256
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
                 asmgen.out("""
-                    ldy  $counterLabel
-                    iny
-                    cpy  #${length and 255}
-                    beq  $endLabel
-                    bne  $loopLabel
-$counterLabel       .byte  0
+$indexVar           .byte  0
 $endLabel""")
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
-                // TODO: optimize loop code when the length of the array is 255 or less instead of 256
                 val length = decl.arraysize!!.size()!! * 2
-                val counterLabel = asmgen.makeLabel("for_counter")    // todo allocate dynamically, zero page preferred if len >= 16
-                val modifiedLabel = asmgen.makeLabel("for_modified")
-                val modifiedLabel2 = asmgen.makeLabel("for_modified2")
+                val indexVar = asmgen.makeLabel("for_index")    // todo allocate dynamically, zero page preferred if length >= 16
                 val loopvarName = asmgen.asmIdentifierName(stmt.loopVar)
                 asmgen.out("""
-                    lda  #<$iterableName
-                    ldy  #>$iterableName
-                    sta  $modifiedLabel+1
-                    sty  $modifiedLabel+2
-                    lda  #<$iterableName+1
-                    ldy  #>$iterableName+1
-                    sta  $modifiedLabel2+1
-                    sty  $modifiedLabel2+2
                     ldy  #0
-$loopLabel          sty  $counterLabel
-$modifiedLabel      lda  ${65535.toHex()},y       ; modified
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
                     sta  $loopvarName
-$modifiedLabel2     lda  ${65535.toHex()},y       ; modified
+                    lda  $iterableName+1,y
                     sta  $loopvarName+1""")
                 asmgen.translate(stmt.body)
+                if(length<=127) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 128 words, 256 bytes
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
                 asmgen.out("""
-                    ldy  $counterLabel
-                    iny
-                    iny
-                    cpy  #${length and 255}
-                    beq  $endLabel
-                    bne  $loopLabel
-$counterLabel       .byte  0
+$indexVar           .byte  0
 $endLabel""")
             }
             DataType.ARRAY_F -> {
diff --git a/examples/test.p8 b/examples/test.p8
index 08c9043eb..fdbaae2cd 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -6,51 +6,48 @@
 main {
 
     sub start() {
-;        byte[] data = [11,22,33,44,55,66]
-;        word[] dataw = [1111,2222,3333,4444,5555,6666]
-;
-;        byte d
-;        word w
-;
-;        for d in data {
-;            c64scr.print_b(d)
-;            c64.CHROUT(',')
-;        }
-;        c64.CHROUT('\n')
-;        for w in dataw {
-;            c64scr.print_w(w)
-;            c64.CHROUT(',')
-;        }
-;        c64.CHROUT('\n')
+        byte[] data = [11,22,33,44,55,66]
+        ubyte[256] data256 = 1
+        word[] dataw = [1111,2222,3333,4444,5555,6666]
+        uword[128] dataw128 = 1
 
+        ubyte u
+        byte d
+        word w
+        uword uw
 
-        ubyte bb
-        ubyte from = 10
-        ubyte end = 20
-
-        for bb in from to end step 3 {
-            c64scr.print_ub(bb)
-            c64.CHROUT(',')
-        }
-        c64.CHROUT('\n')
-        for bb in end to from step -3 {
-            c64scr.print_ub(bb)
+        for u in "hello" {
+            c64scr.print_ub(u)
             c64.CHROUT(',')
         }
         c64.CHROUT('\n')
 
-        word ww
-        word fromw = -10
-        word endw = 21
-
-        for ww in fromw to endw step 3 {
-            c64scr.print_w(ww)
+        for d in data {
+            c64scr.print_b(d)
             c64.CHROUT(',')
         }
-
         c64.CHROUT('\n')
-        for ww in endw to fromw step -3 {
-            c64scr.print_w(ww)
+
+        data256[0]=0
+        data256[254]=254
+        data256[255]=255
+        for u in data256 {
+            c64scr.print_ub(u)
+            c64.CHROUT(',')
+        }
+        c64.CHROUT('\n')
+
+        for w in dataw {
+            c64scr.print_w(w)
+            c64.CHROUT(',')
+        }
+        c64.CHROUT('\n')
+
+        dataw128[0] = 0
+        dataw128[126] =126
+        dataw128[127] =127
+        for uw in dataw128 {
+            c64scr.print_uw(uw)
             c64.CHROUT(',')
         }
         c64.CHROUT('\n')