more consistent about the system reset routine

compiler/res/prog8lib/c64/syslib.p8

@@ -259,6 +259,16 @@ asmsub  init_system()  {
     }}
 }
 
+asmsub  reset_system()  {
+    ; Soft-reset the system back to Basic prompt.
+    %asm {{
+        sei
+        lda  #14
+        sta  $01        ; bank the kernal in
+        jmp  (c64.RESET_VEC)
+    }}
+}
+
 asmsub  set_irqvec_excl() clobbers(A)  {
 	%asm {{
 		sei

compiler/res/prog8lib/cx16/syslib.p8

@@ -277,4 +277,15 @@ asmsub init_system()  {
     }}
 }
 
+asmsub  reset_system()  {
+    ; Soft-reset the system back to Basic prompt.
+    %asm {{
+        sei
+        lda  #14
+        sta  $01
+        stz  cx16.d1prb         ; bank the kernal in
+        jmp  (cx16.RESET_VEC)
+    }}
+}
+
 }

compiler/res/prog8lib/cx16/textio.p8

@@ -154,6 +154,13 @@ asmsub  scroll_left  (ubyte dummy @ Pc) clobbers(A, Y)  {
 	; ---- scroll the whole screen 1 character to the left
 	;      contents of the rightmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag is a dummy on the cx16
+	%asm {{
+	    phx
+	    jsr  c64.SCREEN
+
+	    plx
+	    rts
+	}}
 }
 
 asmsub  scroll_right  (ubyte dummy @ Pc) clobbers(A)  {
@@ -166,6 +173,7 @@ asmsub  scroll_up  (ubyte dummy @ Pc) clobbers(A, Y)  {
 	; ---- scroll the whole screen 1 character up
 	;      contents of the bottom row are unchanged, you should refill/clear this yourself
 	;      Carry flag is a dummy on the cx16
+	; TODO maybe a version without using intermediate buffer is faster? (avoid double store/read)
 	%asm {{
 	    phx
 	    jsr  c64.SCREEN
@@ -265,6 +273,7 @@ asmsub  scroll_down  (ubyte dummy @ Pc) clobbers(A, Y)  {
 	; ---- scroll the whole screen 1 character down
 	;      contents of the top row are unchanged, you should refill/clear this yourself
 	;      Carry flag is a dummy on the cx16
+	; TODO maybe a version without using intermediate buffer is faster? (avoid double store/read)
 	%asm {{
 	    phx
 	    jsr  c64.SCREEN

compiler/src/prog8/compiler/target/CompilationTarget.kt

@@ -17,8 +17,8 @@ internal interface CompilationTarget {
     fun encodeString(str: String, altEncoding: Boolean): List<Short>
     fun decodeString(bytes: List<Short>, altEncoding: Boolean): String
     fun asmGenerator(program: Program, errors: ErrorReporter, zp: Zeropage, options: CompilationOptions, path: Path): IAssemblyGenerator
-    val asmForSystemReset: String
     val initProcName: String?
+    val resetProcName: String?
 
     companion object {
         lateinit var instance: CompilationTarget
@@ -35,8 +35,8 @@ internal object C64Target: CompilationTarget {
             if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
     override fun asmGenerator(program: Program, errors: ErrorReporter, zp: Zeropage, options: CompilationOptions, path: Path) =
             AsmGen(program, errors, zp, options, path)
-    override val asmForSystemReset = "  sei |  lda  #14 |  sta  $1 |  jmp  (c64.RESET_VEC)"
     override val initProcName = "c64.init_system"
+    override val resetProcName = "c64.reset_system"
 }
 
 internal object Cx16Target: CompilationTarget {
@@ -48,6 +48,6 @@ internal object Cx16Target: CompilationTarget {
             if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
     override fun asmGenerator(program: Program, errors: ErrorReporter, zp: Zeropage, options: CompilationOptions, path: Path) =
             AsmGen(program, errors, zp, options, path)
-    override val asmForSystemReset = "  sei |  stz  cx16.d1prb |  jmp  (cx16.RESET_VEC)"
     override val initProcName = "cx16.init_system"
+    override val resetProcName = "cx16.reset_system"
 }

compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt

@@ -163,7 +163,7 @@ internal class AsmGen(private val program: Program,
             }
             Zeropage.ExitProgramStrategy.SYSTEM_RESET -> {
                 out("  jsr  main.start\t; call program entrypoint")
-                out(CompilationTarget.instance.asmForSystemReset)
+                out("  jmp  ${CompilationTarget.instance.resetProcName}")
             }
         }
     }

examples/test.p8

@@ -1,7 +1,7 @@
 %import syslib
 ; %import graphics
 %import textio
-%zeropage basicsafe
+; %zeropage basicsafe
 
 
 main {
@@ -16,9 +16,9 @@ main {
 ;            }
 ;        }
 
-        repeat 60 {
-            txt.setcc(rnd() % 80, 59, 81, 5)
-            txt.scroll_up(true)
+        repeat txt.DEFAULT_WIDTH {
+            txt.setcc(txt.DEFAULT_WIDTH-1, rnd() % txt.DEFAULT_HEIGHT, 81, 2)
+            txt.scroll_left(true)
 
             repeat 5000 {
                 x++