KEY_COUNT := $D0 ; Number of keys in input buffer
FKEY_COUNT := $D1 ; Characters for function key
MODE := $D7 ; 40-/80-column mode (bit 7: 80 columns)
+GRAPHM := $D8 ; Graphics mode flags (bits 5-7)
+CHARDIS := $D9 ; Bit 2 shadow for location $01
CURS_X := $EC ; Cursor column
CURS_Y := $EB ; Cursor row
SCREEN_PTR := $E0 ; Pointer to current char in text screen
RVS := $F3 ; Reverse output flag
SCROLL := $F8 ; Disable scrolling flag
-BASIC_BUF := $200 ; Location of command-line
+BASIC_BUF := $0200 ; Location of command-line
BASIC_BUF_LEN = 162 ; Maximum length of command-line
-FETCH := $2A2 ; Fetch subroutine in RAM
-FETVEC := $2AA ; Vector patch location for FETCH
-STASH := $2AF ; Stash routine in RAM
-STAVEC := $2B9 ; Vector patch location for STASH
-IRQInd := $2FD ; JMP $0000 -- used as indirect IRQ vector
-PALFLAG := $A03 ; $FF=PAL, $00=NTSC
-INIT_STATUS := $A04 ; Flags: Reset/Restore initiation status
+FETCH := $02A2 ; Fetch subroutine in RAM
+FETVEC := $02AA ; Vector patch location for FETCH
+STASH := $02AF ; Stash routine in RAM
+STAVEC := $02B9 ; Vector patch location for STASH
+IRQInd := $02FD ; JMP $0000 -- used as indirect IRQ vector
+PALFLAG := $0A03 ; $FF=PAL, $00=NTSC
+INIT_STATUS := $0A04 ; Flags: Reset/Restore initiation status
+VM2 := $0A2D ; VIC-IIe shadow for $D018 -- graphics mode
FKEY_LEN := $1000 ; Function key lengths
FKEY_TEXT := $100A ; Function key texts
-KBDREPEAT := $28a
-KBDREPEATRATE := $28b
-KBDREPEATDELAY := $28c
+KBDREPEAT := $028a
+KBDREPEATRATE := $028b
+KBDREPEATDELAY := $028c
; ---------------------------------------------------------------------------
; Kernal routines
;
; Based on Stephen L. Judd's GRLIB code.
;
-; 2017-01-13, Greg King
; 2018-03-13, Sven Klose
; 2018-07-22, Scott Hutter
+; 2018-07-28, Greg King
;
.include "zeropage.inc"
.include "tgi-kernel.inc"
.include "tgi-error.inc"
+ .include "c128.inc"
.macpack generic
.macpack module
POINT := regsave
CHUNK := X2 ; Used in the line routine
-OLDCHUNK := X2+1 ; Dito
+OLDCHUNK := X2+1 ; Ditto
; Absolute variables used in the code
BITMASK: .res 1 ; $00 = clear, $FF = set pixels
-; INIT/DONE
-OLDD018: .res 1 ; Old register value
-
; Line routine stuff
DX: .res 2
DY: .res 2
; BAR variables
X1SAVE: .res 2
-Y1SAVE: .res 2
+Y1SAVE: .res 1
X2SAVE: .res 2
-Y2SAVE: .res 2
+Y2SAVE: .res 1
; Text output stuff
TEXTMAGX: .res 1
BITTAB: .byte $80,$40,$20,$10,$08,$04,$02,$01
BITCHUNK: .byte $FF,$7F,$3F,$1F,$0F,$07,$03,$01
-CHARROM := $D000 ; Character rom base address
-CBASE := $5C00 ; Color memory base address
-VBASE := $6000 ; Video memory base address
- ; BASE + $4000 for each bank above VIC bank 0
- ; $2000 = VIC bank 0 (base)
- ; $6000 = VIC bank 1
- ; $A000 = VIC bank 2
- ; $E000 = VIC bank 3
+CHARROM := $D000 ; Character ROM base address
+VBASE := $C000 ; Video memory base address
+CBASE := $E000 ; Color memory base address
.code
;
INIT:
-; Initialize variables
- ldx #$FF
+
+; Initialize variables.
+
+ ldx #$FF ; Foreground color
stx BITMASK
-; Switch into graphics mode
-
- ; select video bank
- ; bank 0=3 ($0-$3FFF) (default)
- ; bank 1=2 ($4000-$7FFF) *
- ; bank 2=1 ($8000-$BFFF)
- ; bank 3=0 ($C000-$FFFF)
- lda $DD00
- and #$FC
- ora #$02 ; bank number 1 ($4000)
- sta $DD00
-
- ; Switch to bitmap mode
- lda $D8
- ora #$20
- sta $D8
-
-DONE1: lda #TGI_ERR_OK
+; Switch into graphics mode.
+
+; Select a video bank:
+; bank 0 = $03 ($0000-$3FFF) (default)
+; bank 1 = $02 ($4000-$7FFF)
+; bank 2 = $01 ($8000-$BFFF)
+; bank 3 = $00 ($C000-$FFFF) (TGI)
+
+ lda CIA2_PRA
+ and #<~$03 ; Bank 3
+ sta CIA2_PRA
+
+ lda #$80 ; color-map at $E000, bitmap at $C000
+ sta VM2
+
+; Make the VIC-IIe read RAM instead of the font ROM.
+
+ lda #%00000100
+ sta CHARDIS
+
+; Switch to bitmap mode.
+
+ lda #%00100000
+ sta GRAPHM
+
+ lda #TGI_ERR_OK
sta ERROR
rts
; Must set an error code: NO
;
-DONE: ; select video bank
- lda $DD00
- and #$FC
- ora #$03 ; bank 0=3 ($0-$3FFF), 1=2 ($4000-$7FFF), 2=1 ($8000-$BFFF), 3=0 ($C000-$FFFF)
- sta $DD00
+DONE:
+
+; Select the text video bank.
- lda $0A2D ; change screen ram location
- AND #$0F
- ORA #$10 ; $0400
- STA $0A2D
+ lda CIA2_PRA
+ ora #$03 ; Bank 0
+ sta CIA2_PRA
- LDA #$00 ; switch back to text mode
- STA $D8
+; Make the VIC-IIe read the font ROM instead of RAM.
+
+ lda #%00000000
+ sta CHARDIS
+
+ ;lda #%00000000 ; Switch back to text mode
+ sta GRAPHM
+
+; Restore a value that's needed by BASIC's GRAPHIC 1 statement.
+
+ lda #$78 ; color-map at $1C00, bitmap at $2000
+ sta VM2
rts
; ------------------------------------------------------------------------
; Must set an error code: NO
;
-CLEAR:
- ldy #$00
+CLEAR:
+ ldy #$00
tya
+ ldx #MMU_CFG_RAM0
+ sei
+ stx MMU_CR
@L1: sta VBASE+$0000,y
sta VBASE+$0100,y
sta VBASE+$0200,y
sta VBASE+$1C00,y
sta VBASE+$1D00,y
sta VBASE+$1E00,y
- sta VBASE+$1E40,y ; preserve vectors
+ sta VBASE+$1F00,y
iny
bne @L1
+ ldx #MMU_CFG_CC65
+ stx MMU_CR
+ cli
rts
; ------------------------------------------------------------------------
asl a
asl a
ora PALETTE ; Background color
- tax
; Initialize the color map with the new color settings (it is below the
-; I/O area)
+; Kernal ROM).
ldy #$00
+ ldx #MMU_CFG_RAM0
sei
- lda $01 ; Get ROM config
- pha ; Save it
- and #%11111100 ; Clear bit 0 and 1
- sta $01
- txa ; Load color code
+ stx MMU_CR
@L2: sta CBASE+$0000,y
sta CBASE+$0100,y
sta CBASE+$0200,y
sta CBASE+$02e8,y
iny
bne @L2
- pla
- sta $01
+ ldx #MMU_CFG_CC65
+ stx MMU_CR
cli
; Done, reset the error code
SETPIXEL:
jsr CALC ; Calculate coordinates
- sei ; Get underneath ROM
- lda $01
- pha
- lda #$34
- sta $01
+ lda #MMU_CFG_RAM0 ; Work behind ROMs
+ sei
+ sta MMU_CR
lda (POINT),Y
eor BITMASK
eor (POINT),Y
sta (POINT),Y
- pla
- sta $01
+ ldx #MMU_CFG_CC65
+ stx MMU_CR
cli
-@L9: rts
+ rts
; ------------------------------------------------------------------------
; GETPIXEL: Read the color value of a pixel and return it in A/X. The
GETPIXEL:
jsr CALC ; Calculate coordinates
- sei ; Get underneath ROM
- lda $01
- pha
- lda #$34
- sta $01
+ lda #MMU_CFG_RAM0 ; Work behind ROMs
+ sei
+ sta MMU_CR
lda (POINT),Y
- ldy #$00
and BITTAB,X
beq @L1
- iny
+ lda #$01 ; Foreground color
-@L1: pla
- sta $01
+@L1: ldy #MMU_CFG_CC65
+ sty MMU_CR
cli
-
- tya ; Get color value into A
ldx #$00 ; Clear high byte
rts
sta OLDCHUNK
sta CHUNK
- sei ; Get underneath ROM
- lda #$34
- sta $01
+ lda #MMU_CFG_RAM0 ; Work behind ROMs
+ sei
+ sta MMU_CR
ldx DY
cpx DX ;Who's bigger: dy or dx?
and CHUNK
eor (POINT),y
sta (POINT),y
- lda #$36
- sta $01
+ ldx #MMU_CFG_CC65
+ stx MMU_CR
cli
rts
lsr CHUNK ;Advance to last point
jsr LINEPLOT ;Plot the last chunk
- lda #$36
- sta $01
+ ldx #MMU_CFG_CC65
+ stx MMU_CR
cli
rts
;
; the original C wrapper and could be written much smaller (besides that,
; calling LINE is not a good idea either).
-BAR: lda Y2
- sta Y2SAVE
- lda Y2+1
- sta Y2SAVE+1
-
+BAR:
lda X2
sta X2SAVE
lda X2+1
sta X2SAVE+1
- lda Y1
- sta Y1SAVE
- lda Y1+1
- sta Y1SAVE+1
+ lda Y2
+ sta Y2SAVE
lda X1
sta X1SAVE
lda X1+1
sta X1SAVE+1
-@L1: lda Y1
- sta Y2
- lda Y1+1
+ lda Y1
+ sta Y1SAVE
+
+@L1: sta Y2
+ lda #>200
+ sta Y1+1
sta Y2+1
+
jsr LINE
- lda Y1SAVE
- cmp Y2SAVE
- bne @L2
lda Y1SAVE
cmp Y2SAVE
beq @L4
-@L2: inc Y1SAVE
- bne @L3
- inc Y1SAVE+1
-
-@L3: lda Y1SAVE
- sta Y1
- lda Y1SAVE+1
- sta Y1+1
+ inc Y1SAVE
lda X1SAVE
sta X1
sta X2
lda X2SAVE+1
sta X2+1
+
+ lda Y1SAVE
+ sta Y1
jmp @L1
@L4: rts
projects / cc65 / commitdiff