57 lines
734 B
NASM
57 lines
734 B
NASM
cpu 8086
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self: equ 0xF000
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diskbuf: equ (self-0x200) ; deblocking
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stack: equ (diskbuf) ; grows down
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defdrv: equ 4
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org self
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jmp init
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pad 3
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self_offset:
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db (self >> 8)
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banner:
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db "RDOS 2019-09", 0x0A, 0x0D, '$', 0
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init:
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mov sp, stack
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mov byte [defdrv], 0x01
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mov dx, banner
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call print_string
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call exec_chain
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cli
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.halt:
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hlt
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jmp .halt
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init_program:
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db "HELLO.COM", 0
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cpm_syscall:
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cmp cl, 0
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je init
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cmp cl, 1
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je console_input
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cmp cl, 2
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je console_output
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cmp cl, 9
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je print_string
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cmp cl, 10
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je read_buffer
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stc
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ret
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%include "char.asm"
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%include "exec.asm"
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%include "fdc.asm"
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%include "fcb.asm"
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%include "fcbparse.asm"
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%include "drive.asm"
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%include "log2.asm"
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%include "dump.asm"
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