選択できるのは25トピックまでです。
トピックは、先頭が英数字で、英数字とダッシュ('-')を使用した35文字以内のものにしてください。
135 行
2.5 KiB
135 行
2.5 KiB
#generate 16-bit code
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.code16
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#hint the assembler that here is the executable code located
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.text
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.globl _start;
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#boot code entry
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_start:
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welcome: .asciz "Welcome to this very fine Guessing game \n\r" #here we define the string
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enter_number: .asciz "Enter a number: \n"
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lower_msg: .asciz "Your number is to low :( \n" # 26
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higher_msg: .asciz "Your number is to high :( \n" # 27
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winner_msg: .asciz "Your are the CAMPION, :D \n" # 26
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.macro mWriteString str #macro which calls a function to print a string
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leaw \str, %si
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call .writeStringIn
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.endm
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#jmp _boot
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# function to print the string
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.writeStringIn:
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lodsb
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orb %al, %al
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jz .writeStringOut
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movb $0x0e, %ah
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int $0x10
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jmp .writeStringIn
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.writeStringOut:
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ret #jump to boot code
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mWriteString welcome
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/*
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guess:
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call get_number
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xor %ah, %ah
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call string_to_int
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cmp $5, %dx
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jl if_lower # rax less then 50
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je if_eg
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jg if_higher
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if_lower:
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mWriteString lower_msg
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jmp guess
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if_higher:
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mWriteString higher_msg
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jmp guess
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if_eg:
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mWriteString winner_msg #message length
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hlt
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*/
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#_boot:
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# mWriteString welcome
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#.type string_to_int, @function
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#string_to_int:
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/* Converts a string to an integer. Returns the integer in %rax.
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* %rax: Address of string to convert.
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*/
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/*
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push %bp
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mov %sp, %bp
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push %bx
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push %cx
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mov %ax, %dx
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xor %ax, %ax
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cmp $47, %dx
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jl not_a_num
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cmp $57, %dx
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jg not_a_num
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# I multiply by 10 to shift the number one placement to the right to add the newest integer.
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sub $48, %dx # In ascii, numbers start at 0 = 48, 1 = 49, 2 = 50 and so on. So I subtract 48 to get the digit.
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not_a_num:
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xor %dx, %dx
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convertdone:
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pop %cx
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pop %bx
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mov %bp, %sp
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pop %bp
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ret
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.type get_number, @function
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get_number:
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# .enter_char:
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# mov $0, %ah
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# mov $0, %al
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# int $0x16
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# mov $0x0E, %ah
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# int $0x10
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# jmp .enter_char
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# save state before function
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push %bp
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mov %sp, %bp
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push %bx
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push %cx
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# Start of function
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mWriteString enter_number
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mov $0, %ah
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mov $0, %al
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int $0x16
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mov $0x0E, %ah
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int $0x10
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pop %cx
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pop %bx
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mov %bp, %sp
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pop %bp
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ret
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*/
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#move to 510th byte from the start and append boot signature
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. = _start + 510
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.byte 0x55
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.byte 0xaa
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