; ========================================================================================
; Print8 params Print (x,y,a)
; p1: a ascii r8 ascii character, 0-255
align 16
export Print8: ; print an 8x8 pet 8032 text character @(x,y)
sub rsp, 28h
mov [rsp+00h], rsi
mov [rsp+08h], rdi
mov [rsp+10h], rbx
mov [rsp+18h], rbp
; ---- Enter -----
; 1. src
; get a ptr to the font data
mov esi, FONT8$ ; ptr to font sets in emulator ram @ $E000
; get offset to font bitmap data (char# * 8 bytes/char)
mov ebx, r8d ; get char#
shl ebx, 3 ; mult char# x 8 bytes per char
add esi, ebx ; rsi: points to param character's bitmap data
; 2. dst
mov edi, VIDEO$ ; base
; add (x,y) offsets
mov eax, [CursorX8] ; get (x)
mov ebx, [CursorY8] ; get (y)
shl eax, 2 ; x-offset = x * 4
shl ebx, 13 ; y-offset = y * 2000h
add edi, eax ; add x-offset to base surface
add edi, ebx ; add y-offset to base address
mov ebp, edi ; copy print address to rowptr
mov r10d, [BGcolor8] ; get bg color
mov r11d, [FGcolor8] ; get fg color
; 3. ----- the print loop -----
mov dl, 8 ; init rowctr (8 rows, 8 pixels each)
do8rows: ; 8-bit processing of one screen row of char data
mov al, [esi] ; ax = get bitmap data for 1 screen row (8 pixels, 1 byte)
mov cl, 8 ; init pixelctr = 8 pixels per screen row
do8pixels: ; 8 shifts = 1 row (1 byte) of pixel data, poke on 1-bits only
shl al, 1 ; shift bit 7 into carry flag
cmovnc ebx, r10d ; when bit = 0, use bg color
cmovc ebx, r11d ; when bit = 1, use fg color
mov [edi], ebx ; poke the color to surface memory
add edi, 4 ; advance to next x-pixel (right 1)
dec cl ; pixelctr = pixelctr-1
jnz < do8pixels ; loop until pixelctr = 0
; re-sync the pointers for the next row (down 1)
add esi, 1 ; advance fontptr to next source row (+pitch = 1 byte)
add ebp, 2000h ; rowptr + pitch = next row
mov edi, ebp ; copy rowptr to colptr
dec dl ; rowctr = rowctr-1
jnz < do8rows ; loop until rowctr = 0
add D[CursorX8], 8 ; get CursorX8 ready for next Print: +8 pixels
; ----- Exit -----
mov rsi, [rsp+00h]
mov rdi, [rsp+08h]
mov rbx, [rsp+10h]
mov rbp, [rsp+18h]
add rsp, 28h
ret
; ========================================================================================
; Plot8(x,y)
; p1: x
; p2: y
align 16
export Plot8:
mov [CursorX8], r8d
mov [CursorY8], r9d
ret
; ========================================================================================
; SetTextColor8(bg_color,fg_color)
; p1: bg color
; p2: fg color
align 16
export SetTextColor8:
mov [BGcolor8], r8d
mov [FGcolor8], r9d
ret
; ========================================================================================
; SetFont8(font_num)
; p1: font# (0 = serif, 1 = sans)
align 16
export SetFont8:
mov [FontNum8], r8d
ret
; ========================================================================================
; String8 String8 (x,y,pStringz)
; p1: pStringz r8 ptr to text string
align 16
export String8: ; String prints a 0-term ascii string
sub rsp, 18h
mov [rsp+00h], rsi ; preserve
mov [rsp+08h], rbx ; preserve
; ----- Enter -----
; loop to print a 0-term string
mov esi, r8d ; copy of the string ptr
xor ebx, ebx ; init string length index = 0
strloop8:
movzx r8d, B[esi + ebx] ; get a character from the string (r8 = param for Print)
or r8d, r8d ; check to see if character = 0
jz > strExit8 ; if yes, exit
call Print8 ; print the character in r8
inc ebx ; increment string length index
jnz < strloop8 ; always loop back for more
; ----- Exit -----
strExit8:
mov rsi, [rsp+00h] ; restore
mov rbx, [rsp+08h] ; restore
add rsp, 18h
ret
; ========================================================================================
; Print8DecD (n)
; p1: n x r8
align 16
export Print8DecD:
sub rsp, 18h
mov [rsp+00h], rsi ; save (x) for String16
mov [rsp+08h], rdi ; save (y) for String16
mov [rsp+10h], rbx
; ----- ENTER -----
lea edi, textBuffer + 15 ; Point RDI to the last byte of the buffer
mov B[edi], 0 ; Null-terminate the string
dec edi ; Move to the previous byte
mov ebx, 10 ; Divisor for base-10 conversion
mov eax, r8d ; number to convert (can be any unsigned 32-bit value)
; Handle the special case of 0
test eax, eax
jnz > convert_loop8
mov B[rdi], '0'
jmp > donep8
convert_loop8:
xor edx, edx ; Clear EDX for division (EDX:EAX / EBX)
div ebx ; EAX = EAX / 10, EDX = remainder (0-9)
add dl, '0' ; Convert remainder to ASCII
mov [edi], dl ; Store ASCII digit
dec edi ; Move backward in buffer
test eax, eax
jnz < convert_loop8 ; Repeat if quotient is not zero
donep8:
inc edi ; RDI now points to the first digit
; At this point, RDI points to the start of the null-terminated string in textBuffer
; Print the string
mov r8d, edi ; ptr to number string
call String8 ; print the string
; ----- EXIT -----
mov rsi, [rsp+00h]
mov rdi, [rsp+08h]
mov rbx, [rsp+10h]
add rsp, 18h ; fix the stack
ret
; ========================================================================================
; Print8HexB (n)
; p1: n r8
align 16
export Print8HexB:
call dw2hex ; convert to an ascii string
lea r8d, textBuffer+6 ; address of the number as a text string
call String8 ; print the number
ret
; ========================================================================================
; Print8HexW (n)
; p1: n r8
export align 16
Print8HexW:
call dw2hex ; convert to an ascii string
lea r8d, textBuffer+4 ; address of the number as a text string
call String8 ; print the number
ret
;=========================================================================
; Print8HexD (n)
; p1: n r8
align 16
export Print8HexD:
call dw2hex ; convert to an ascii string
lea r8d, textBuffer ; address of the number as a text string
call String8 ; print the number
ret
;=========================================================================
; Print8BinB (n)
; p1: n r8
align 16
export Print8BinB:
call dw2bin ; convert to an ascii string
lea r8d, textBuffer+24 ; address of the number as a text string
call String8 ; print the number
ret
;=========================================================================
; Print8BinW (n)
; p1: n r8
align 16
export Print8BinW:
call dw2bin ; convert to an ascii string
lea r8, textBuffer+16 ; address of the number as a text string
call String8 ; print the number
ret
;=========================================================================
; Print8BinD (n)
; p1: n r8
align 16
export Print8BinD:
call dw2bin ; convert to an ascii string
lea r8, textBuffer ; address of the number as a text string
call String8 ; print the number
ret
;=========================================================================
