diff options
Diffstat (limited to 'portstat.s')
| -rw-r--r-- | portstat.s | 56 |
1 files changed, 55 insertions, 1 deletions
@@ -1,5 +1,12 @@ - .export _port_stat_screen + .export _port_stat_screen, _redraw_port_stat + .import _port_stat_dirty + .importzp ptr1, ptr2 + + srcptr = ptr1 + dstptr = ptr2 + + .include "atari.inc" ; PORTSTAT.DAT is created on the H: device by running mkportstats.xex ; in atari800. H: needs to be set writable and pointed to the current @@ -8,3 +15,50 @@ .rodata _port_stat_screen: .incbin "PORTSTAT.DAT" +screenlen = * - _port_stat_screen +screenpages = >screenlen +partial = <screenlen + + .code + +; only redraw the port status screen if needed. this saves 53 bytes +; compared to using memcpy(). +; void redraw_port_stat(void); +_redraw_port_stat: + lda _port_stat_dirty + beq @done + + lda #<_port_stat_screen + sta srcptr + lda #>_port_stat_screen + sta srcptr+1 + + lda SAVMSC + sta dstptr + lda SAVMSC+1 + sta dstptr+1 + + ; copy screenpages pages + ldx #screenpages + ldy #0 +@pageloop: + lda (srcptr),y + sta (dstptr),y + dey + bne @pageloop + inc srcptr+1 + inc dstptr+1 + dex + bne @pageloop + + ; copy last (partial) page. we know Y is 0 here. + sty _port_stat_dirty +@partloop: + lda (srcptr),y + sta (dstptr),y + iny + cpy #partial + bne @partloop + +@done: + rts |