==== Opening the top and bottom borders ==== This is a clever trick for you to try on the C64. Demos in the 1980's and 1990's and probably still today use the opened borders technique. I am going to show you how to do a simple border opening technique in ACME crossassembler format. ;Opening the top + bottom borders ;inside an IRQ interrupt player !to "borders.prg" * = $0810 ;SYS 2064 to run it sei lda #$02 sta $d020 lda #$00 sta $d021 lda #irq1 sta $315 lda #$7f sta $dc0d lda #$1b sta $d011 lda #$01 sta $d01a cli jmp * irq1: inc $d019 lda #$00 sta $d012 lda #$00 sta $d011 lda #irq2 sta $315 jmp $ea7e irq2: inc $d019 lda #$fa sta $d012 lda #$1b ;If you want to display a bitmap pic, use #$3b instead sta $d011 lda #irq1 sta $315 jmp $ea7e