9dd460a47f
This bootloader right now just prints the letter A, but should be capable of reading blocks from the SD card into memory.
27 lines
370 B
ArmAsm
27 lines
370 B
ArmAsm
; We need to to read the boot sector from the
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; SD card, verify the last 2 bytes, then jump to the
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; beginning of it.
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.include "zeropage.inc"
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.import _load_bootsect
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.export _init, _boot
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.segment "STARTUP"
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_init: jmp _boot
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.segment "CODE"
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_boot: ldx #$ff
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txs
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cld
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jsr _load_bootsect
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jmp $1000
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.segment "SIGN"
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.byte $55
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.byte $aa
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