Untitled

ORG $60000       ; Set memory origin to address $60000

screen_width    equ 320         ; Screen width in pixels
screen_height   equ 200         ; Screen height in pixels
color           equ $0FFF       ; Example color value (white)

start:
    move.w  #color, d0         ; Load color value into register d0
    move.l  #screen_memory, a0 ; Load address of screen memory into register a0
    moveq   #0, d1              ; Clear jitter counter
    move.w  #0, d2              ; Clear line counter

draw_loop:
    move.b  d0, (a0)+           ; Draw pixel with current color
    addq.w  #1, d1              ; Increment jitter counter
    cmp.w   #4, d1              ; Check if jitter counter reached maximum
    bne     .skip_jitter        ; If not, skip jitter effect
    addq.l  #1, a0              ; Apply jitter effect (shift to the right)
    moveq   #0, d1              ; Reset jitter counter
.skip_jitter:
    cmp.w   #screen_width, d1   ; Check if reached end of line
    bne     .next_pixel         ; If not, proceed to next pixel
    addq.w  #1, d2              ; Increment line counter
    move.l  #screen_memory, a0  ; Reset screen memory pointer to beginning of line
    add.l   #screen_width, a0   ; Move to next line
    moveq   #0, d1              ; Reset jitter counter
.next_pixel:
    cmp.w   #screen_height, d2  ; Check if reached end of screen
    bne     draw_loop           ; If not, continue drawing
    bra     start               ; Restart the effect

screen_memory   equ $0000       ; Address of screen memory

END start