Apple-2-SW/Applecorn
1
0
Fork 0
mirror of https://github.com/bobbimanners/Applecorn.git synced 2025-01-23 01:29:53 +00:00
Code Issues Projects Releases Wiki Activity

Fix HGR scrolling corruption with ISR #199

Browse Source
This commit is contained in:
Bobbi Webber-Manners 2022-12-21 20:35:59 -05:00
parent e228883700
commit 754271b618
1 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
mainmem.hgr.s
View File

@ -146,6 +146,8 @@ DRAWCHAR >>> ENTMAIN
* Copy text line A+1 to line A
HGRSCR1L >>> ENTMAIN
PHP ; Disable interrupts ..
SEI ; .. to prevent corruption while scrolling
INC MTXTWINRGT
ASL ; Dest addr->A4L,A4H
TAX
@ -177,6 +179,7 @@ DOHGRSCR1L LDX #$00
INX
CPX #8 ; 8 pixel rows in character
BNE :L1
PLP ; Re-enable interrupts
>>> XF2AUX,HSCR1RET
* Copy text line A to line A+1