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.
60 lines
1.0 KiB
ArmAsm
60 lines
1.0 KiB
ArmAsm
.importzp sp, sreg
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.import _uart_txb_block
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.import _lastchar
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.export _cputc
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.export gotoxy
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.export _clrscr
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.export _cgetc
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.autoimport on
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.code
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; void __fastcall__ cputc (char c);
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_cputc:
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jsr _uart_txb_block
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cmp #$0a
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bne @1
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lda #$0d
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jsr _uart_txb_block
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@1: rts
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; void __fastcall__ gotoxy (unsigned char x, unsigned char y);
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gotoxy:
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phx
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phy
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tay ; Move y position to y
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lda (sp)
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tax ; Move x position to x
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lda #$1b
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jsr _uart_txb_block
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lda #'['
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jsr _uart_txb_block
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tya
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jsr _uart_txb_block
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lda #';'
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jsr _uart_txb_block
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txa
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jsr _uart_txb_block
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lda #'H'
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jsr _uart_txb_block
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ply
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plx
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rts
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_clrscr:
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phx
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lda #$1b
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jsr _uart_txb_block
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lda #'c'
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jsr _uart_txb_block
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pla
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rts
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_cgetc:
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@2: lda _lastchar
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beq @2
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stz _lastchar
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rts |