and use display list copy in aligned memory

This commit is contained in:
Brooke Vibber 2023-01-22 07:36:08 -08:00
parent 6fc07b9e65
commit 335c4d2c96

View file

@ -24,10 +24,11 @@ FR1 = $e0
FR2 = $e6
; High data
framebuffer_top = $8000
framebuffer_top = $8000
textbuffer = $8f00
framebuffer_bottom = $9000
textbuffer = $9f00
framebuffer_end = $a000
display_list = $9f00
framebuffer_end = $a000
height = 184
half_height = height >> 1
@ -104,7 +105,7 @@ bit_masks:
.byte 3 << 4
.byte 3 << 6
display_list:
display_list_start:
; 48 lines overscan
.repeat 5
.byte $70 ; 8 blank lines
@ -129,6 +130,8 @@ display_list:
.byte $41 ; jump and blank
.addr display_list
display_list_end:
display_list_len = display_list_end - display_list_start
.code
@ -528,14 +531,6 @@ done:
; Disable display DMA
sta DMACTL
; Set up the display list
lda #.lobyte(display_list)
sta DLISTL ; actual register
sta SDLSTL ; shadow register the OS will copy in
lda #.hibyte(display_list)
sta DLISTH ; actual register
sta SDLSTH ; shadow register the OS will copy in
; zero the range from framebuffer_top to framebuffer_end
lda #.lobyte(framebuffer_top)
sta temp
@ -555,6 +550,24 @@ zero_byte_loop:
cmp #.hibyte(framebuffer_end)
bne zero_page_loop
; Copy the display list into properly aligned memory
; Can't cross 1024-byte boundaries :D
ldx #0
copy_byte_loop:
lda display_list_start,x
sta display_list,x
inx
cpx #display_list_len
bne copy_byte_loop
; Set up the display list
lda #.lobyte(display_list)
sta DLISTL ; actual register
sta SDLSTL ; shadow register the OS will copy in
lda #.hibyte(display_list)
sta DLISTH ; actual register
sta SDLSTH ; shadow register the OS will copy in
; Status bar
draw_text 0, str_self_len, str_self
draw_text 40 - str_run_len, str_run_len, str_run