29 lines
583 B
ArmAsm
29 lines
583 B
ArmAsm
; Debug Bootblock - Green Screen Loop
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MACHINE 68000
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ORG 0
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dc.b 'D','O','S',0 ; DOS magic
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dc.l 0 ; Checksum
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dc.l 880 ; Rootblock
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; Boot code
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DMACON EQU $096
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COLOR00 EQU $180
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boot_start:
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; Direct hardware access to set color
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lea $dff000,a6 ; Custom Chips Base
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; Disable DMA to be safe
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move.w #$7FFF,DMACON(a6)
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; Set Background Color to GREEN
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move.w #$0F0,COLOR00(a6)
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.loop:
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; Infinite loop
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bra.s .loop
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; Pad to 1024 bytes
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dcb.b 1024-(*-0),0
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