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;TODO fix null problem, allow direct passes
bios_print:
;push ax ; we need to use ax, so let's push it in case whoever called needs it
pusha
mov ah, 0x0e ; tells bios we're in tty mode
.print_loop:
mov al, [bx] ; al is the char MEANT TO BE CX
cmp al, 0 ; compare the char we're about to print with null
je .fini ; if it is null, we gonna scoot the fuck outta here
test cx, cx ; if cx is zero, ascii, otherwise hex string
jne .print_hex
int 0x10 ; bios call, actually prints the char
.print_hex_ret:
inc bx ; adds to the pointer
jmp .print_loop ; goes back to loop start
.fini:
mov al, 0xd ; \r
int 0x10
mov al, 0xa ; \n
int 0x10
popa
ret
.print_hex:
mov al, '0'
int 0x10
mov al, 'x'
int 0x10
mov al, [bx] ; shift bits to get first nibble
shr al, 4
call .bios_print_nibble
mov al, [bx]
and al, 0x0f
call .bios_print_nibble
mov al, ' '
int 0x10
jmp .print_hex_ret
.bios_print_nibble:
cmp al, 9 ; see if letter worthy
ja .print_hex_letter
add al, 0x30 ;'1'
int 0x10
ret
.print_hex_letter:
add al, 0x57 ;'a'
int 0x10
ret
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