Apple-2-SW/emailler
1
0
Fork 0
mirror of https://github.com/bobbimanners/emailler.git synced 2025-04-27 14:37:05 +00:00
Code Issues Projects Releases Wiki Activity

Implemented reverse scroll for Videx.

Browse Source
This commit is contained in:
Bobbi Webber-Manners 2024-08-10 23:34:01 -04:00
parent fab6169b59
commit e50fb5a89e
1 changed files with 61 additions and 3 deletions

64
drivers/a2vt100.s

@ -25,7 +25,6 @@ videx = 1
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; TODO for VIDEX
; - Reverse scroll (fast and slow)
; - Keybindings for { } \ ` ~ _ -- Maybe use Escape prefix ??
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@ -1517,7 +1516,7 @@ VidexSetCurs
adc #00 ; Now cVector has row * 80 + col
sta cVector+1 ; For cursor
clc
clc ; Add the display base address
lda cVector
adc BASEL
sta cVector
@ -1774,6 +1773,7 @@ UScrl
rts
; Slow software scrolling
; y = SRS
US1 ldx #$00 ; First column
US2 stx zVector ; Use zVector as temporary for x
sty zVector+1 ; Use zVector+1 as temporary for y
@ -1856,7 +1856,65 @@ DS3 lda (xVector),y ; copy char
rts
.else
DScrl
; TODO - Write me
ldy SRE ; If SRS==0 && SRE==23, use hardware scrolling
cmp #23
bne DS1
lda SRS
bne DS1
; Fast hardware scrolling
lda START ; Load start address from screen hole
sec
sbc #$05 ; Go up one row (5*16 bytes=80)
sta START ; Update start address in screen hole
pha ; Save for later
lsr ; Mult*16 - for MSbyte
lsr ; ..
lsr ; ..
lsr ; ..
ldx #12 ; Register 12 - MSbyte of start address
stx SL3DEV0
sta SL3DEV1
sta BASEH ; Stash in screen hole
pla ; Recover row * 5 + start
asl ; Mult*16 - for LSbyte
asl ; ..
asl ; ..
asl ; ..
ldx #13 ; Register 13 - LSbyte of start address
stx SL3DEV0
sta SL3DEV1
sta BASEL ; Stash in screen hole
ldy #0 ; First line
jsr ErLn_ ; Delete first line
rts
; Slow software scrolling
; y = SRE
DS1 ldx #$00 ; First column
DS2 stx zVector ; Use zVector as temporary for x
sty zVector+1 ; Use zVector+1 as temporary for y
dey ; Copy from row above
jsr VidexSetVec ; Set up pointers
jsr VidexPage ; Page in correct page on Videx
jsr VidexGet ; Get source char
pha ; Stash char for later
ldx zVector ; Recover X
ldy zVector+1 ; Recover Y
jsr VidexSetVec ; Set up pointers
jsr VidexPage ; Page in correct page on Videx
pla ; Recover char
jsr VidexPut ; Copy char to screen
ldx zVector ; Recover X
ldy zVector+1 ; Recover Y
inx ; Next col
cpx #80 ; Last col?
bne DS2
dey ; Next line (going upwards)
cpy SRS ; Last line?
bne DS1 ; Nope, go again
ldy SRS
jsr ErLn_ ; Delete first line (SRS)
rts
.endif