Superogue at 22:35, 28 March 2024

2024-03-28T22:35:21Z

Superogue: Created page with "== Apple II == The Apple II is an 8-bit home computer and one of the world's first highly successful mass-produced microcomputer products. It was designed primarily by Steve W..."

2022-03-10T13:17:05Z

Created page with "== Apple II == The Apple II is an 8-bit home computer and one of the world's first highly successful mass-produced microcomputer products. It was designed primarily by Steve W..."

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== Apple II ==
The Apple II is an 8-bit home computer and one of the world's first highly successful mass-produced microcomputer products. It was designed primarily by Steve Wozniak.

=== Setting up ===
* ACME 6502 cross-assembler(https://sourceforge.net/projects/acme-crossass/)
* Apple Commander (http://applecommander.sourceforge.net) for batch compilation
* AppleWin emulator (https://github.com/AppleWin/AppleWin/releases). Supports Mockingboard card(AY-8910+speech synthesier), HDD, Z80 card(for CP/M), mouse etc.
* CiderPress(https://a2ciderpress.com)

Compilation can be done as follows (master.dsk can be found with applewin)
<syntaxhighlight>
acme hl.asm
java -jar AppleCommander-1.3.5.jar -d master.dsk hl
java -jar AppleCommander-1.3.5.jar -p master.dsk hl B 24576 < hl.bin
</syntaxhighlight>

=== Memory Map ===
<syntaxhighlight lang="6502">
0-255 $0-$FF ZERO-PAGE SYSTEM STORAGE
256-511 $100-$1FF SYSTEM STACK
512-767 $200-$2FF KEYBOARD CHARACTER BUFFER
768-975 $300-$3CF OFTEN AVAILABLE AS FREE SPACE FOR USER PROGRAMS
976-1023 $3D0-3FF SYSTEM VECTORS
1024-2047 $400-$7FF TEXT AND LO-RES GRAPHICS PAGE 1 <--- !!!
2048-LOMEM $800-LOMEM PROGRAM STORAGE
2048-3071 $800-$BFF TEXT AND LO-RES GRAPHICS PAGE 2 OR FREE SPACE
3072-8191 $C00-$1FFF FREE SPACE UNLESS RAM APPLESOFT IS IN USE
8192-16383 $2000-$3FFF HI-RES PAGE 1 OR FREE SPACE <--- !!!
16384-24575 $4000-$5FFF HI-RES PAGE 2 OR FREE SPACE
24576-38999 $6000-$95FF FREE SPACE AND STRING STORAGE
38400-49151 $9600-$BFFF DOS
49152-53247 $C000-$CFFF I/O HARDWARE (RESERVED)
53248-57343 $D000-$DFFF APPLESOFT IN LANGUAGE CARD OR ROM
57344-63487 $E000-$F7FF APPLESOFT OR INTEGER BASIC IN LANGUAGE CARD OR ROM
63488-65535 $F800-$FFFF SYSTEM MONITOR
</syntaxhighlight>

=== Display ===

=== Graphics Modes ===
: Text Mode 40x24, for Apple IIe available 80x25 - use PR#3 for switch mode, or hardware switch
: LowRes 40x48, 16 colors: https://en.wikipedia.org/wiki/Apple_II_graphics
: Hires mode 280x192,6 colors: https://www.xtof.info/blog/?p=768
https://mrob.com/pub/xapple2/colors.html
https://archive.org/details/HiRes_Color_Graphics_on_the_Apple_II_Computer_by_Wozniak

However for sizecoding, you almost never want to do direct-access to graphics for Apple II in size-coding because the Apple II graphics modes are horrible. The only fast way to do things is with large lookup tables. To do hires you need to divide by 7 which as you can imagine is a bit difficult to do compactly on 6502. Double-hires is even crazier on top of that. Deater did manage a color-bar style effect in double-hires in 128B but that was doing some crazy tricks with the firmware BASIC routines, definitely not direct-access.

Lores and Hires can be mixed modes and full-graphics
The screen structure is called memory holes(https://retrocomputing.stackexchange.com/questions/2534/what-are-the-screen-holes-in-apple-ii-graphics). The GBASCALC($F847) procedure is used to calculate the address of the horizontal line : IN:reg.A=Y, out : GBASL/GBASH($26/$27)=address. See also https://www.callapple.org/uncategorized/use-of-apple-ii-color-graphics-in-assembly-language/

==== Getting something on screen ====
Here is an example of a XOR texture, created by g0blinish
<syntaxhighlight lang="6502">
*=$6000
!to "HL.bin", plain ; set output file and format
!cpu 6502 ; set processor type

GBASL = $26
GBASH = $27
SETGR = $FB40 ; setup LoRes
GBASCALC = $F847 ; calc Address

CLRTEXT = $C050 ;display graphics
SETTEXT = $C051 ;display text

CLRMIXED = $C052 ;clear mixed mode- enable full graphics
SETMIXED = $C053 ;enable graphics/text mixed mode

PAGE1 = $C054 ;select text/graphics page1
PAGE2 = $C055 ;select text/graphics page2

CLRHIRES = $C056 ;select Lo-res
SETHIRES = $C057 ;select Hi-res

TMP= $FA

JSR SETGR ;GR
BIT CLRMIXED ; full screen

LDA #0 ; A=0
STA TMP ; POKE $FA,A

YLP ;
LDA TMP ; A=PEEK($FA)
; LSR ; A=A/2
JSR GBASCALC
LDY #0;Y=0

XLP TYA ; A=Y
EOR TMP ; A=A xor PEEK($FA)
and #$0F ; A=A and 15
TAX ; X=A
LDA COLORS,X ;A=PEEK(COLORS+X)
STA(GBASL),Y ; POKE PEEK($26)+256*PEEK($27)+Y,A
INY ; Y=Y+1
CPY #40 ; Y=40?
BNE XLP
INC TMP ; POKE $FA,PEEK($FA)+1
LDA TMP ; A=PEEK($FA)
CMP #24 ; A=24?
BNE YLP

M1 JMP M1 ; replace to RTS

COLORS ;N*17, pixel format is AAAABBBB, AAAA - upper dot, BBBB - lower dot
!byte $00,$11,$22,$33,$44,$55,$66,$77
!byte $88,$99,$AA,$BB,$CC,$DD,$EE,$FF
</syntaxhighlight>

==== Sound ====
Here is an example for using the speaker, based onthe following basic program:

<syntaxhighlight lang="basic">
; 50 POKE 768,V: POKE 769,P - 255 * INT (P / 256): POKE 800,1 + P / 256
; 60 CALL 770: RETURN
; 95 FOR K = 1 TO N: READ V(K),P(K): NEXT K
; 100 FOR K = 1 TO N:V = V(K):P = P(K)
; 110 GOSUB 50
;!byte 173,48,192,136,208,5,206,1,3,240,9,202,208,245,174,0,3,76,2,3,206,32,3,208,240,96
</syntaxhighlight>

<syntaxhighlight lang="6502">
*=$6000
!to "HL.bin", plain ; set output file and format
!cpu 6502 ; set processor type

;start
; 95 FOR K = 1 TO N: READ V(K),P(K): NEXT K
; 100 FOR K = 1 TO N:V = V(K):P = P(K)
ini:
lda #70
sta cnt+1
lda #music&255
sta gotbyte+1
lda #music/256
sta gotbyte+2

lop:
;V
jsr gotbyte
sta L300
jsr gotbyte
;P
jsr gotbyte
sta L301
jsr gotbyte
clc
adc #1
sta L320
jsr beep

dec cnt+1
cnt lda #70
bne lop
; 110 GOSUB 50
; 50 POKE 768,V: POKE 769,P - 255 * INT (P / 256): POKE 800,1 + P / 256
; 60 CALL 770: RETURN
jmp ini
gotbyte
lda music
inc gotbyte+1
bne noinch
inc gotbyte+2
noinch
rts
;!byte 173,48,192,136,208,5,206,1,3,240,9,202,208,245,174,0,3,76,2,3,206,32,3,208,240,96
beep:
ldy #1
ldx #1
loc_302:
LDA $C030

loc_305:
DEY
BNE loc_30D
DEC L301
loc_30B:
BEQ loc_316

loc_30D:
DEX
BNE loc_305
LDX L300
JMP loc_302
loc_316:
DEC L320
BNE loc_30B
RTS
L301 !byte 0
L300 !byte 0
L320 !byte 0
music
!word 76,192,85,64,96,64,102,64,114,128,114,64,96,64,102,64,114,64,128,64
!word 114,64,152,64,171,64,152,512,76,192,85,64,96,64,102,64,114,128,114,64
!word 96,64,102,64,114,64,128,64,114,64,152,64,171,64,152,512,85,64,85,64
!word 85,64,96,64,144,128,144,64,128,64,76,128,85,64,96,64,144,128,114,64
!word 96,64,102,128,114,64,128,64,128,128,114,64,128,64,114,512,85,64,85,64
!word 85,64,96,64,144,128,144,64,128,64,76,128,85,64,96,64,144,128,114,64
!word 96,64,102,128,114,64,128,64,128,64,128,128,96,64,85,64,96,64,102,64,114,64,114,64
</syntaxhighlight>

=== Additional Resources ===
* Deater's page on Apple II sizecoding http://www.deater.net/weave/vmwprod/demos/sizecoding.html (with an additional presentation at https://www.youtube.com/watch?v=kJ-EXbnw0kQ )
* Article on double hi-res http://www.battlestations.zone/2017/04/apple-ii-double-hi-res-from-ground-up.html
* Applesoft Hi-Res Subroutines : http://hackzapple.org/scripts_php/index.php?menu=5&mod=ASM&sub=AAL&sub2=8112&PHPSESSID=f65fabfd0cdbf56b6bdc0ddac25117c6#a2

@@ Line 4: / Line 4: @@
 === Setting up ===
 * ACME 6502 cross-assembler(https://sourceforge.net/projects/acme-crossass/)
 * Apple Commander (http://applecommander.sourceforge.net) for batch compilation
 * AppleWin emulator (https://github.com/AppleWin/AppleWin/releases). Supports Mockingboard card(AY-8910+speech synthesier), HDD, Z80 card(for CP/M), mouse etc.

Apple II - Revision history

Superogue at 22:35, 28 March 2024

Superogue: Created page with "== Apple II == The Apple II is an 8-bit home computer and one of the world's first highly successful mass-produced microcomputer products. It was designed primarily by Steve W..."