vdl macro

2026-05-20 22:34:21 +02:00 · 2023-01-31 16:35:02 -05:00
parent f703316128
commit a64d01067d
1 changed files with 22 additions and 0 deletions
@@ -51,6 +51,28 @@
         STX $0201
         STA NMIEN
         .ENDM
+;-------------------------------------
+        .MACRO VDL
+;   VDL #WORD
+;   Changes Display List addres
+; and sets width of the screen
+;    vdl dl,$01 - narrow screen (32 bytes)
+;    vdl dl,$02 - normal screen (40 bytes)
+;    vdl dl,$03 - wide screen   (48 bytes)
+;       (works only with system interrupts ON)
+
+         .if %0=2
+           lda dmactls
+           and #$fc
+           ora #%2
+           sta dmactls
+         .endif
+
+         LDA # <%1
+         STA DLPTRS
+         LDA # >%1
+         STA DLPTRS+1
+         .ENDM
 ;-------------------------------------
      .MACRO halt
 ?stop