2008-08-24 01:18:20 +00:00
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; Apple 1 emulator for SAM Coupe, by Simon Owen
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;
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2008-09-05 10:58:10 +00:00
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; Version 1.2 (5/9/2008)
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2007-04-02 13:21:49 +00:00
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;
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; WWW: http://simonowen.com/sam/apple1emu/
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2008-09-05 17:43:42 +00:00
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base: equ &d000 ; Emulator code shares Apple 1 I/O area
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2008-08-24 01:18:20 +00:00
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status: equ &f9 ; Status and extended keyboard port
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lmpr: equ &fa ; Low Memory Page Register
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hmpr: equ &fb ; High Memory Page Register
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vmpr: equ &fc ; Video Memory Page Register
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keyboard: equ &fe ; Keyboard port
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border: equ &fe ; Border port
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2007-04-02 13:21:49 +00:00
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rom0_off: equ %00100000 ; LMPR bit to disable ROM0
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rom1_on: equ %01000000 ; LMPR bit to enable ROM1
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vmpr_mode2: equ %00100000 ; Mode 2 select for VMPR
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low_page: equ 3 ; LMPR during emulation
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screen_page: equ 5 ; SAM display
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file_page: equ 6 ; File import text page
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m6502_nmi: equ &fffa ; nmi vector address
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m6502_reset: equ &fffc ; reset vector address
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m6502_int: equ &fffe ; int vector address (also for BRK)
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2008-09-05 17:43:42 +00:00
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r1onclbc: equ &01ea ; ROM 1 on, call BC
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2008-08-24 01:18:20 +00:00
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getkey: equ &1cab ; SAM ROM key reading (NZ=got key in A, A=0 for no key)
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2007-04-02 13:21:49 +00:00
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2008-09-05 17:43:42 +00:00
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; PIA registers for keyboard and display I/O
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2007-04-02 13:21:49 +00:00
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kbd_data: equ &d010 ; keyboard data
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kbd_ctrl: equ &d011 ; keyboard control
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dsp_data: equ &d012 ; display data
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dsp_ctrl: equ &d013 ; display control
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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org base
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dump $
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autoexec
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2008-09-05 17:43:42 +00:00
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di
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jr start
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2007-04-02 13:21:49 +00:00
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2008-09-05 17:43:42 +00:00
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defs kbd_data-$
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; This gap contains the PIA locations from above
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defs dsp_ctrl-kbd_data+1
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start: ld a,low_page+rom0_off
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2007-04-02 13:21:49 +00:00
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out (lmpr),a
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ld a,vmpr_mode2+screen_page
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out (vmpr),a
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2008-09-05 17:43:42 +00:00
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ld (basic_stack),sp
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2007-04-02 13:21:49 +00:00
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ld sp,stack_top
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call set_sam_attrs ; set the mode 2 attrs so the screen is visible
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call setup_im2 ; enable IM 2
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2008-09-05 17:43:42 +00:00
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ld a,(op_00) ; lowest address used by emulator
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ld (rom_write+1),a ; save byte to restore to simulate ROM
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2007-04-02 13:21:49 +00:00
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reset_loop: ld hl,0
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ld (dsp_data),hl ; display ready
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2008-07-20 12:52:56 +00:00
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ld (kbd_data),hl ; no key available
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2007-04-02 13:21:49 +00:00
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ld hl,(m6502_reset) ; start from reset vector
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ld (reg_pc),hl
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2008-08-24 01:18:20 +00:00
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ld a,&04 ; interrupts disabled
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ld (reg_p),a
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2007-04-02 13:21:49 +00:00
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ei
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2008-08-24 01:18:20 +00:00
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call load_state
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2007-04-02 13:21:49 +00:00
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call execute ; GO!
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2008-08-24 01:18:20 +00:00
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call save_state
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2007-04-02 13:21:49 +00:00
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jr reset_loop
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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; Utility functions
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; Fill SAM mode 2 display attributes to make the screen visible
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set_sam_attrs: ld a,screen_page+rom0_off
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out (lmpr),a
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ld hl,&2000
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ld bc,&1844 ; 24 blocks of bright green on black
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clear_lp: ld (hl),c
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inc l
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jr nz,clear_lp
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inc h
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djnz clear_lp
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ld a,low_page+rom0_off
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out (lmpr),a
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ret
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; Scroll the screen up 1 row and clear the bottom line
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scroll_screen: ld hl,0
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ld d,h
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ld e,l
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inc h
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ld bc,&1700
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scroll_lp: FOR 32, ldi ; 32 * LDI
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jp pe,scroll_lp
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dec h
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scroll_clr: ld (hl),0
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inc l
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jp nz,scroll_clr
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ret
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; Advance the cursor 1 character, wrapping and scrolling if necessary
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advance_chr: ld hl,(cursor_xy)
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cp &5f
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jr z,back_chr
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cp &0a
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jr z,advance_line
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cp &0d
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jr z,advance_line
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ld a,l
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add a,6
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ld l,a
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cp &f0
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jr c,no_wrap
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advance_line: ld l,0
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inc h
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ld a,h
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cp &18
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jr nz,no_wrap
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dec h
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exx
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call scroll_screen
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exx
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no_wrap: ld (cursor_xy),hl
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ret
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back_chr: ld a,l
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sub 6
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ld l,a
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jr nc,no_wrap
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ld l,39*6
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ld a,h
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sub 1
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adc a,0
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ld h,a
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jr no_wrap
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; Map display character from SAM to Apple 1
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2008-09-05 10:58:10 +00:00
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map_chr: sub &20
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ret nc
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xor a
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2007-04-02 13:21:49 +00:00
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ret
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; Display character in A at current cursor position
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display_chr: add a,a ; * 2
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ld l,a
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ld h,0
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2008-09-05 10:58:10 +00:00
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add hl,hl ; * 4
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2007-04-02 13:21:49 +00:00
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add hl,hl ; * 8
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ld de,font_data
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add hl,de
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ld d,mask_data/256
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exx
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ld hl,(cursor_xy)
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ld a,l
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and %00000111
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srl l
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srl l
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srl l
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inc l
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exx
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ld e,a
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exx
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ld de,&0020
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ld b,8
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draw_lp: exx
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ld c,(hl)
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inc l
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xor a
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cp e
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jr z,no_rot
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ld b,e
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rot_lp: srl c
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rra
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djnz rot_lp
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no_rot: ld b,a
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ld a,(de)
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inc e
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exx
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and (hl)
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inc l
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exx
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or c
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ex af,af'
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ld a,(de)
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dec e
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exx
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and (hl)
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exx
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or b
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exx
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ld (hl),a
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dec l
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ex af,af'
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ld (hl),a
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add hl,de
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djnz draw_lp
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ret
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; LSB=pixel position (0-240), MSB=display row (0-23)
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cursor_xy: defw 0
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; Map key symbols from SAM to Apple 1
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map_key: cp &0c
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jr z,del_key
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cp &fc
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jr z,tab_key
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cp &80
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jr nc,ignore_key
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cp &61 ; 'a'
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ret c
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cp &7b ; 'z'+1
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ret nc
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and %11011111
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ret
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del_key: ld a,&5f ; Delete -> _
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ret
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tab_key: ld a,&09 ; standard tab
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ret
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invalid_key: ld a,&20 ; space for invalid
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ret
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ignore_key: xor a ; ignore
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ret
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; Get a type-in key from the imported file
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get_filekey: ld a,file_page+rom0_off
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out (lmpr),a
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ld hl,(filepos)
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ld a,h
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or l
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or (hl)
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jr z,file_done ; jump if no file
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file_skip: ld a,(hl) ; fetch next file character
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inc hl
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and a
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jr z,clear_file2 ; clear file at end
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cp &0d ; CR?
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jr z,file_skip ; ignore CR in file
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cp &0a ; LF?
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jr nz,file_done
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ld a,&0d ; convert LF to CR
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file_done: ld (filepos),hl
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and a
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ret
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filepos: defw 0
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; Clear the file area to disable type-in
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clear_file: ld a,file_page+rom0_off
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out (lmpr),a
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clear_file2: ld hl,0
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ld c,l
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clr_file_lp: ld (hl),c
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inc l
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jr nz,clr_file_lp
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inc h
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bit 7,h
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jr nz,clr_file_lp
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ld h,l
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xor a ; no file character
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jr file_done
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update_io:
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ld a,&f7
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in a,(status)
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and %00100000
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jr nz,not_esc ; jump if Esc not pressed
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call clear_file ; Esc cancels type-in mode
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ld a,&fe
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in a,(keyboard)
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rra
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2008-07-20 12:52:56 +00:00
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jr c,not_reset ; unshifted gives chr
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ld a,&c9 ; RET opcode
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ld (main_loop),a ; return to reset on next instruction
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not_reset:
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2007-04-02 13:21:49 +00:00
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2008-07-20 12:52:56 +00:00
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still_esc: ld a,&f7
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in a,(status)
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and %00100000
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jr z,still_esc ; wait until Esc released
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ld a,&1b ; Esc character
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jr got_key
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2007-04-02 13:21:49 +00:00
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not_esc:
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ld a,&7f
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in a,(keyboard)
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bit 1,a
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jr nz,not_sym
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ld a,&f7
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in a,(keyboard)
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rra
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ld c,&ff ; line interrupt disable
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jr nc,got_line
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rra
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ld c,88 ; centre of display (312/2-68=88)
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jr c,not_sym
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got_line: ld a,c
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out (status),a ; set or disable line interrupt
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not_sym:
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ld hl,kbd_ctrl
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bit 7,(hl) ; key available?
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jr nz,no_key ; no need to read more yet
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call get_filekey ; got a type-in key from file?
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jr nz,got_key ; jump if we have
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2008-09-05 17:43:42 +00:00
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skip_key: ld a,&1f ; LMPR page for BASIC, with ROM 0 enabled
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2007-04-02 13:21:49 +00:00
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out (lmpr),a
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2008-09-05 17:43:42 +00:00
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ld (save_stack),sp
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ld sp,(basic_stack)
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ld bc,getkey ; return key code in A, zero for none
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call r1onclbc
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ld sp,(save_stack)
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2007-04-02 13:21:49 +00:00
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jr z,no_key
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call map_key
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and a
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jr z,skip_key
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got_key:
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ld hl,kbd_data
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ld (hl),a
|
|
|
|
|
set 7,(hl) ; bit 7 always set
|
|
|
|
|
inc l
|
|
|
|
|
set 7,(hl) ; key available
|
|
|
|
|
no_key:
|
|
|
|
|
ld hl,dsp_data
|
|
|
|
|
bit 7,(hl) ; display char available?
|
|
|
|
|
jr z,no_char
|
|
|
|
|
res 7,(hl) ; display ready
|
|
|
|
|
ld a,(hl) ; fetch character to display
|
|
|
|
|
and a
|
|
|
|
|
jr z,done_draw
|
|
|
|
|
cp &7f
|
|
|
|
|
jr z,done_draw
|
|
|
|
|
push af
|
2008-09-05 17:43:42 +00:00
|
|
|
ld a,screen_page+rom0_off
|
|
|
|
|
out (lmpr),a ; page in screen
|
2007-04-02 13:21:49 +00:00
|
|
|
ld a,&00 ; space
|
|
|
|
|
call display_chr ; erase cursor
|
|
|
|
|
pop af
|
|
|
|
|
cp &5f ; backspace? (underscore)
|
|
|
|
|
jr z,done_draw2 ; if so, no need to process further
|
|
|
|
|
|
|
|
|
|
push af
|
|
|
|
|
call map_chr ; map output from SAM->Apple 1
|
|
|
|
|
call display_chr ; show it
|
|
|
|
|
pop af
|
|
|
|
|
done_draw2: call advance_chr ; advance the cursor position
|
2008-09-05 10:58:10 +00:00
|
|
|
ld a,&5f ; cursor block
|
2007-04-02 13:21:49 +00:00
|
|
|
call display_chr ; show cursor
|
|
|
|
|
done_draw:
|
|
|
|
|
no_char:
|
|
|
|
|
ret
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
|
|
|
|
|
|
; Interrupt handling
|
|
|
|
|
|
|
|
|
|
setup_im2: ld hl,im2_table
|
|
|
|
|
ld a,im2_jp/256
|
|
|
|
|
im2_fill: ld (hl),a
|
|
|
|
|
inc l
|
|
|
|
|
jr nz,im2_fill
|
|
|
|
|
inc h
|
|
|
|
|
ld (hl),a ; complete the final entry
|
|
|
|
|
ld a,im2_table/256
|
|
|
|
|
ld i,a
|
|
|
|
|
im 2 ; set interrupt mode 2
|
|
|
|
|
ret
|
|
|
|
|
|
|
|
|
|
im2_handler: push af
|
|
|
|
|
push bc
|
|
|
|
|
push de
|
|
|
|
|
push hl
|
|
|
|
|
ex af,af'
|
|
|
|
|
exx
|
|
|
|
|
push af
|
|
|
|
|
push bc
|
|
|
|
|
push de
|
|
|
|
|
push hl
|
|
|
|
|
push ix
|
|
|
|
|
push iy
|
|
|
|
|
|
|
|
|
|
in a,(lmpr)
|
|
|
|
|
push af
|
|
|
|
|
call update_io
|
|
|
|
|
pop af
|
|
|
|
|
out (lmpr),a
|
|
|
|
|
|
|
|
|
|
pop iy
|
|
|
|
|
pop ix
|
|
|
|
|
pop hl
|
|
|
|
|
pop de
|
|
|
|
|
pop bc
|
|
|
|
|
pop af
|
|
|
|
|
exx
|
|
|
|
|
ex af,af'
|
|
|
|
|
pop hl
|
|
|
|
|
pop de
|
|
|
|
|
pop bc
|
|
|
|
|
pop af
|
|
|
|
|
ei
|
|
|
|
|
reti
|
2008-08-24 02:19:42 +00:00
|
|
|
|
2007-04-02 13:21:49 +00:00
|
|
|
|
|
|
|
|
; IM 2 table must be aligned to 256-byte boundary
|
|
|
|
|
defs -$\256
|
|
|
|
|
im2_table: defs 257
|
|
|
|
|
|
|
|
|
|
; IM 2 vector must have LSB==MSB
|
|
|
|
|
defs $/256-1
|
|
|
|
|
stack_top: ; stack fits nicely in the slack space
|
|
|
|
|
im2_jp: jp im2_handler
|
|
|
|
|
|
2008-09-05 17:43:42 +00:00
|
|
|
basic_stack: defw 0
|
|
|
|
|
save_stack: defw 0
|
|
|
|
|
|
2007-04-02 13:21:49 +00:00
|
|
|
|
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
|
|
|
|
|
|
; 65C02 emulation
|
|
|
|
|
|
|
|
|
|
execute: ld a,&1a ; LD A,(DE)
|
2008-08-24 01:18:20 +00:00
|
|
|
ld (ix),a
|
|
|
|
|
jp (ix)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
i_undoc_3: inc de ; 3-byte NOP
|
|
|
|
|
i_undoc_2: inc de ; 2-byte NOP
|
2008-09-05 10:58:10 +00:00
|
|
|
i_undoc_1: jp (ix) ; NOP
|
2008-08-24 01:18:20 +00:00
|
|
|
|
2007-04-02 13:21:49 +00:00
|
|
|
|
|
|
|
|
read_write_loop:
|
|
|
|
|
write_loop: ld a,h
|
2008-09-05 17:43:42 +00:00
|
|
|
cp op_00/256 ; MSB of lowest emulator byte
|
2008-09-05 10:58:10 +00:00
|
|
|
jr nc,write_trap
|
2007-04-02 13:21:49 +00:00
|
|
|
|
|
|
|
|
zwrite_loop:
|
2008-08-24 01:18:20 +00:00
|
|
|
main_loop: ld a,(de) ; 7/7/15 - fetch opcode
|
|
|
|
|
inc de ; 6/7/11 - PC++
|
|
|
|
|
ld l,a ; 4/6/6 - LSB is opcode
|
|
|
|
|
ld h,msb_table/256 ; 7/7/15 - look-up table
|
|
|
|
|
ld h,(hl) ; 7/8/16 - opcode MSB
|
|
|
|
|
jp (hl) ; 4/5/9 - execute!
|
|
|
|
|
; = 35T (official) / 40T (off-screen) / 72T (on-screen)
|
|
|
|
|
|
2008-09-05 17:43:42 +00:00
|
|
|
write_trap: cp &d0 ; I/O page?
|
|
|
|
|
jr nz,rom_write
|
2008-09-05 10:58:10 +00:00
|
|
|
ld a,l
|
2007-04-02 13:21:49 +00:00
|
|
|
cp &12 ; display char?
|
2008-08-24 01:18:20 +00:00
|
|
|
jr z,chr_write
|
|
|
|
|
jp (ix)
|
|
|
|
|
chr_write: set 7,(hl) ; display busy
|
|
|
|
|
jp (ix)
|
2007-04-02 13:21:49 +00:00
|
|
|
|
2008-09-05 17:43:42 +00:00
|
|
|
rom_write: ld a,&00 ; patched by starting code
|
|
|
|
|
ld (op_00),a ; emulator appears read-only to be ROM for RAM tests
|
2008-09-05 10:58:10 +00:00
|
|
|
jp (ix)
|
|
|
|
|
|
2008-08-24 01:18:20 +00:00
|
|
|
read_loop: ld a,h
|
2007-04-02 13:21:49 +00:00
|
|
|
cp &d0
|
2008-08-24 01:18:20 +00:00
|
|
|
jr z,read_trap
|
2007-04-02 13:21:49 +00:00
|
|
|
|
|
|
|
|
ld a,(de) ; fetch opcode
|
2008-08-24 01:18:20 +00:00
|
|
|
inc de ; PC++
|
|
|
|
|
ld l,a ; LSB is opcode
|
|
|
|
|
ld h,msb_table/256 ; look-up table
|
|
|
|
|
ld h,(hl) ; opcode MSB
|
2007-04-02 13:21:49 +00:00
|
|
|
jp (hl) ; execute!
|
|
|
|
|
|
2008-08-24 01:18:20 +00:00
|
|
|
read_trap: ld a,l
|
2007-04-02 13:21:49 +00:00
|
|
|
cp &10 ; key read?
|
2008-08-24 01:18:20 +00:00
|
|
|
jr z,key_read
|
2007-04-02 13:21:49 +00:00
|
|
|
jp (ix)
|
2008-08-24 01:18:20 +00:00
|
|
|
key_read: inc l
|
|
|
|
|
res 7,(hl) ; key not available
|
2007-04-02 13:21:49 +00:00
|
|
|
jp (ix)
|
|
|
|
|
|
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
|
|
|
|
|
|
load_state: ld a,(reg_a)
|
|
|
|
|
ld b,a ; set A
|
|
|
|
|
ld a,(reg_x)
|
2007-06-26 13:57:28 +00:00
|
|
|
ld iyh,a ; set X to IYh
|
2007-04-02 13:21:49 +00:00
|
|
|
ld a,(reg_y)
|
2007-06-26 13:57:28 +00:00
|
|
|
ld iyl,a ; set Y to IYl
|
2007-04-02 13:21:49 +00:00
|
|
|
exx
|
|
|
|
|
ld a,(reg_s)
|
|
|
|
|
ld l,a ; set S
|
|
|
|
|
ld h,&01 ; MSB for stack pointer
|
|
|
|
|
ld a,(reg_p)
|
2008-08-24 01:18:20 +00:00
|
|
|
ld c,a ; keep safe
|
|
|
|
|
and %00001100 ; keep D and I
|
|
|
|
|
or %00110000 ; force T and B
|
|
|
|
|
ld d,a ; set P
|
|
|
|
|
ld a,c
|
|
|
|
|
and %01000000 ; keep V
|
|
|
|
|
ld e,a ; set V
|
|
|
|
|
ld a,c
|
|
|
|
|
rra ; carry from C
|
|
|
|
|
ex af,af' ; set carry
|
|
|
|
|
ld a,c
|
|
|
|
|
and %10000010 ; keep N Z
|
|
|
|
|
xor %00000010 ; zero for Z
|
|
|
|
|
exx
|
|
|
|
|
ld c,a ; set N Z
|
2007-04-02 13:21:49 +00:00
|
|
|
ld de,(reg_pc) ; set PC
|
2008-08-24 01:18:20 +00:00
|
|
|
ld ix,main_loop ; decode loop
|
2007-04-02 13:21:49 +00:00
|
|
|
ret
|
|
|
|
|
|
|
|
|
|
save_state: ld a,b ; get A
|
|
|
|
|
ld (reg_a),a
|
2007-06-26 13:57:28 +00:00
|
|
|
ld a,iyh ; get X from IYh
|
2007-04-02 13:21:49 +00:00
|
|
|
ld (reg_x),a
|
2007-06-26 13:57:28 +00:00
|
|
|
ld a,iyl ; get Y from IYl
|
2007-04-02 13:21:49 +00:00
|
|
|
ld (reg_y),a
|
2008-08-24 01:18:20 +00:00
|
|
|
ex af,af' ; carry
|
|
|
|
|
inc c
|
|
|
|
|
dec c ; set N Z
|
|
|
|
|
push af ; save flags
|
|
|
|
|
ex af,af' ; protect carry
|
2007-04-02 13:21:49 +00:00
|
|
|
exx
|
2008-08-24 01:18:20 +00:00
|
|
|
pop bc
|
|
|
|
|
ld a,c
|
|
|
|
|
and %10000001 ; keep Z80 N and C
|
|
|
|
|
bit 6,c ; check Z80 Z
|
|
|
|
|
jr z,save_nz
|
|
|
|
|
or %00000010 ; set Z
|
|
|
|
|
save_nz: or e ; merge V
|
|
|
|
|
or d ; merge T B D I
|
|
|
|
|
ld (reg_p),a
|
2007-04-02 13:21:49 +00:00
|
|
|
ld a,l ; get S
|
|
|
|
|
ld (reg_s),a
|
|
|
|
|
exx
|
|
|
|
|
ld (reg_pc),de
|
|
|
|
|
ret
|
|
|
|
|
|
2008-08-24 01:18:20 +00:00
|
|
|
|
|
|
|
|
; During running we keep the 65xx registers in Z80 registers
|
|
|
|
|
; These are used only to hold the state before/after running
|
2007-04-02 13:21:49 +00:00
|
|
|
reg_a: defb 0
|
|
|
|
|
reg_p: defb 0
|
|
|
|
|
reg_x: defb 0
|
|
|
|
|
reg_y: defb 0
|
|
|
|
|
reg_s: defb 0
|
|
|
|
|
reg_pc: defw 0
|
|
|
|
|
|
2008-08-24 01:18:20 +00:00
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
2007-04-02 13:21:49 +00:00
|
|
|
|
2008-08-24 01:18:20 +00:00
|
|
|
defs -$\256
|
2007-04-02 13:21:49 +00:00
|
|
|
|
2008-08-24 01:18:20 +00:00
|
|
|
msb_table: defb op_00>>8, op_01>>8, op_02>>8, op_03>>8, op_04>>8, op_05>>8, op_06>>8, op_07>>8
|
|
|
|
|
defb op_08>>8, op_09>>8, op_0a>>8, op_0b>>8, op_0c>>8, op_0d>>8, op_0e>>8, op_0f>>8
|
|
|
|
|
defb op_10>>8, op_11>>8, op_12>>8, op_13>>8, op_14>>8, op_15>>8, op_16>>8, op_17>>8
|
|
|
|
|
defb op_18>>8, op_19>>8, op_1a>>8, op_1b>>8, op_1c>>8, op_1d>>8, op_1e>>8, op_1f>>8
|
|
|
|
|
defb op_20>>8, op_21>>8, op_22>>8, op_23>>8, op_24>>8, op_25>>8, op_26>>8, op_27>>8
|
|
|
|
|
defb op_28>>8, op_29>>8, op_2a>>8, op_2b>>8, op_2c>>8, op_2d>>8, op_2e>>8, op_2f>>8
|
|
|
|
|
defb op_30>>8, op_31>>8, op_32>>8, op_33>>8, op_34>>8, op_35>>8, op_36>>8, op_37>>8
|
|
|
|
|
defb op_38>>8, op_39>>8, op_3a>>8, op_3b>>8, op_3c>>8, op_3d>>8, op_3e>>8, op_3f>>8
|
|
|
|
|
defb op_40>>8, op_41>>8, op_42>>8, op_43>>8, op_44>>8, op_45>>8, op_46>>8, op_47>>8
|
|
|
|
|
defb op_48>>8, op_49>>8, op_4a>>8, op_4b>>8, op_4c>>8, op_4d>>8, op_4e>>8, op_4f>>8
|
|
|
|
|
defb op_50>>8, op_51>>8, op_52>>8, op_53>>8, op_54>>8, op_55>>8, op_56>>8, op_57>>8
|
|
|
|
|
defb op_58>>8, op_59>>8, op_5a>>8, op_5b>>8, op_5c>>8, op_5d>>8, op_5e>>8, op_5f>>8
|
|
|
|
|
defb op_60>>8, op_61>>8, op_62>>8, op_63>>8, op_64>>8, op_65>>8, op_66>>8, op_67>>8
|
|
|
|
|
defb op_68>>8, op_69>>8, op_6a>>8, op_6b>>8, op_6c>>8, op_6d>>8, op_6e>>8, op_6f>>8
|
|
|
|
|
defb op_70>>8, op_71>>8, op_72>>8, op_73>>8, op_74>>8, op_75>>8, op_76>>8, op_77>>8
|
|
|
|
|
defb op_78>>8, op_79>>8, op_7a>>8, op_7b>>8, op_7c>>8, op_7d>>8, op_7e>>8, op_7f>>8
|
|
|
|
|
defb op_80>>8, op_81>>8, op_82>>8, op_83>>8, op_84>>8, op_85>>8, op_86>>8, op_87>>8
|
|
|
|
|
defb op_88>>8, op_89>>8, op_8a>>8, op_8b>>8, op_8c>>8, op_8d>>8, op_8e>>8, op_8f>>8
|
|
|
|
|
defb op_90>>8, op_91>>8, op_92>>8, op_93>>8, op_94>>8, op_95>>8, op_96>>8, op_97>>8
|
|
|
|
|
defb op_98>>8, op_99>>8, op_9a>>8, op_9b>>8, op_9c>>8, op_9d>>8, op_9e>>8, op_9f>>8
|
|
|
|
|
defb op_a0>>8, op_a1>>8, op_a2>>8, op_a3>>8, op_a4>>8, op_a5>>8, op_a6>>8, op_a7>>8
|
|
|
|
|
defb op_a8>>8, op_a9>>8, op_aa>>8, op_ab>>8, op_ac>>8, op_ad>>8, op_ae>>8, op_af>>8
|
|
|
|
|
defb op_b0>>8, op_b1>>8, op_b2>>8, op_b3>>8, op_b4>>8, op_b5>>8, op_b6>>8, op_b7>>8
|
|
|
|
|
defb op_b8>>8, op_b9>>8, op_ba>>8, op_bb>>8, op_bc>>8, op_bd>>8, op_be>>8, op_bf>>8
|
|
|
|
|
defb op_c0>>8, op_c1>>8, op_c2>>8, op_c3>>8, op_c4>>8, op_c5>>8, op_c6>>8, op_c7>>8
|
|
|
|
|
defb op_c8>>8, op_c9>>8, op_ca>>8, op_cb>>8, op_cc>>8, op_cd>>8, op_ce>>8, op_cf>>8
|
|
|
|
|
defb op_d0>>8, op_d1>>8, op_d2>>8, op_d3>>8, op_d4>>8, op_d5>>8, op_d6>>8, op_d7>>8
|
|
|
|
|
defb op_d8>>8, op_d9>>8, op_da>>8, op_db>>8, op_dc>>8, op_dd>>8, op_de>>8, op_df>>8
|
|
|
|
|
defb op_e0>>8, op_e1>>8, op_e2>>8, op_e3>>8, op_e4>>8, op_e5>>8, op_e6>>8, op_e7>>8
|
|
|
|
|
defb op_e8>>8, op_e9>>8, op_ea>>8, op_eb>>8, op_ec>>8, op_ed>>8, op_ee>>8, op_ef>>8
|
|
|
|
|
defb op_f0>>8, op_f1>>8, op_f2>>8, op_f3>>8, op_f4>>8, op_f5>>8, op_f6>>8, op_f7>>8
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defb op_f8>>8, op_f9>>8, op_fa>>8, op_fb>>8, op_fc>>8, op_fd>>8, op_fe>>8, op_ff>>8
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2007-04-02 13:21:49 +00:00
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2008-08-24 01:18:20 +00:00
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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2007-04-02 13:21:49 +00:00
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2008-08-24 01:18:20 +00:00
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defs -$\256 ; align to 256-byte boundary
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2007-04-02 13:21:49 +00:00
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2008-09-05 10:58:10 +00:00
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; !"#$%&1()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]`abcdefghijklmnopqrstuvwxyz{|}~
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2007-04-02 13:21:49 +00:00
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font_data:
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2008-09-05 10:58:10 +00:00
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MDAT "font.bin"
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2007-04-02 13:21:49 +00:00
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mask_data: defb %00000011,%11111111
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defb %11000000,%11111111
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defb %11110000,%00111111
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defb %11111100,%00001111
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2008-08-24 01:18:20 +00:00
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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2007-04-02 13:21:49 +00:00
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end: equ $
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length: equ end-start
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2008-08-24 01:18:20 +00:00
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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2008-09-05 10:58:10 +00:00
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; Instruction implementations
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INC "opimpl.inc"
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2008-08-24 01:18:20 +00:00
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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2008-09-05 10:58:10 +00:00
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; Woz Monitor ROM (&ff00-&ffff)
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; May be overwritten by includes below
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dump &ff00
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MDAT "apple1.rom"
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; Use RAM-based Applesoft BASIC by default
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IF 1
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; Applesoft BASIC [Lite] (6000-7FFF)
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; http://cowgod.org/replica1/applesoft/
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dump low_page,&6000
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MDAT "applesoft-lite-0.4-ram.bin"
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ELSE
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; Lee Davidson's Enhanced BASIC (5800-77CE)
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; http://members.lycos.co.uk/leeedavison/6502/ehbasic/
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dump low_page,&5800
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MDAT "ehbasic.bin"
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ENDIF
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; Use Ken Wessen's BASIC+assembler by default
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IF 1
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; Ken Wessen's custom BASIC + Krusader assembler + enhanced monitor (E000-FFFF)
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; BRK handler points to mini-monitor in this version
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; http://school.anhb.uwa.edu.au/personalpages/kwessen/apple1/Krusader.htm
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2007-04-02 13:21:49 +00:00
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dump &e000
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2008-09-05 10:58:10 +00:00
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MDAT "65C02.rom.bin"
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ELSE
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; Applesoft BASIC [Lite] + Woz monitor (E000-FFFF)
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; http://cowgod.org/replica1/applesoft/
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dump &e000
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MDAT "applesoft-lite-0.4.bin"
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ENDIF
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|
2007-04-02 13:21:49 +00:00
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2008-09-05 10:58:10 +00:00
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; Test program to output the character set (5000-500B)
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; LDX $00 ; loop: TXA ; JSR echo ; INX ; BRA loop
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dump low_page,&5000
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defb &a2, &00, &8a, &20, &ef, &ff, &e8, &80, &f9
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