c6098f2d1f
Eventually I want the kernel to be loaded from the SD card as well, but it still needs to separate from user programs. At some point there should be a folder just for the BIOS, which should read from the boot block of the SD card and start executing, and thats it.
33 lines
309 B
ArmAsm
33 lines
309 B
ArmAsm
.include "io.inc65"
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.importzp sp, sreg
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.export _mapper_enable
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.export _mapper_read, _mapper_write
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.autoimport on
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.code
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; void mapper_enable(uint8_t en)
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_mapper_enable:
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sta MM_CTRL
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rts
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_mapper_read:
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phx
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tax
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lda MM_DATA,x
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ldx #$00
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rts
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_mapper_write:
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phx
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tax
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jsr popa
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sta MM_DATA,x
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plx
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rts
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