Files
aqhomecontrol/avr/modules/lcd2/font/font6x8.asm
2025-06-02 21:13:44 +02:00

110 lines
2.8 KiB
NASM

; ***************************************************************************
; copyright : (C) 2025 by Martin Preuss
; email : martin@libchipcard.de
;
; ***************************************************************************
; * This file is part of the project "AqHome". *
; * Please see toplevel file COPYING of that project for license details. *
; ***************************************************************************
; ***************************************************************************
; code
.cseg
; ---------------------------------------------------------------------------
; @routine font6x8MonoHandlerFn
;
; Handler for 6x8 Mono Fonts
;
font6x8MonoHandlerFn:
cpi r23, FONT_FN_RENDER
breq font6x8MonoRenderCharacter
rjmp FONT_GenericHandler
; @end
; ---------------------------------------------------------------------------
; @routine font6x8RenderCharacter
; @param R16 character to write
; @param R1:R0 background color
; @param R3:R2 foreground color
; @param Z pointer to font
; @param X pointer to RAM to store data to
; @param r18 char width in pixel
; @param r19 char height in pixel
; @clobbers r16, r17, r24, r25, x
font6x8MonoRenderCharacter:
push zl
push zh
adiw zh:zl, FONT_OFFS_WIDTH
lpm r18, Z+ ; char width in pixels
lpm r19, Z ; char height in pixels
sbiw zh:zl, FONT_OFFS_WIDTH+1
rcall font6x8GetCharPosInFont ; (r16, r17, r24, r25, z)
mov r25, r19 ; height in pixels
font6x8MonoRenderCharacter_loop1:
mov r24, r18 ; width in pixels
lpm r17, Z+
font6x8MonoRenderCharacter_loop2:
lsr r17
brcs font6x8MonoRenderCharacter_writeForeground
st X+, r0
st X+, r1
rjmp font6x8MonoRenderCharacter_loop2end
font6x8MonoRenderCharacter_writeForeground:
st X+, r2
st X+, r3
font6x8MonoRenderCharacter_loop2end:
dec r24
brne font6x8MonoRenderCharacter_loop2
dec r25
brne font6x8MonoRenderCharacter_loop1
pop zh
pop zl
ret
; @end
; ---------------------------------------------------------------------------
; @routine font6x8GetCharPosInFont (same as font8x8GetCharPosInFont!)
; @param R16 character to write
; @param Z pointer to font
; @return Z pointer to begin of char data
; @clobbers r16, r17, r24, r25, z
font6x8GetCharPosInFont:
mov r24, r16
adiw zh:zl, FONT_OFFS_FIRSTCHAR
lpm r24, Z+ ; first char num
lpm r25, Z+ ; num of chars
sub r16, r24
brcs font6x8GetCharPosInFont_ret
cp r16, r25
brcc font6x8GetCharPosInFont_ret
mov r24, r16
clr r25
lsl r24 ; x2
rol r25
lsl r24 ; x4
rol r25
lsl r24 ; x8
rol r25
add zl, r24
adc zh, r25
font6x8GetCharPosInFont_ret:
ret
; @end