Demo (SDK)

Programs
Assembly: bgcol1 bgcol2 charset ciao fill1 fill2 gamekeys idummy iload ipnggen1 ipnggen2 irawrgba keypad loop1 loop2 loop3 maze resize setpal sprites stdpal tiles vintage C: bounce cciao clock cpubm dpyinfo fps gperf hello mandelbrot newline pngtest rand time

Support Files
c64jb.c cgetc.s chline.s clock.s clrscr.s color.s cputc.s crt0.s ctype.s cvline.s gotox.s gotoxy.s gotoy.s header.s jbit.cfg jbit.h jbit.inc kbhit.s mainargs.s randomize.s vsync.s wherex.s wherey.s _scrsize.s _systime.s

+----------+
|          |
|  JBitRT  |
|  MIDlet  |
| Emulator |
|          |
|  1 2 3   |
|  4 5 6   |
|  7 8 9   |
|  * 0 #   |
|          |
+----------+

charset.jb

; Browse the charset (2=Up, 8=Down and 0=Exit).
; CPU: CLC (CLear Carry), SEC (SEt Carry), ADC (ADd with Carry), \
; SBC (SuBtract with Carry), BCS (Branch on Carry Set), \
; BCC (Branch on Carry Clear).
; Style: This is "spaghetti" code; note how difficult it is \
; to understand how it works. A few tricks have also been \
; used to keep it in 64 bytes (BCC/BCS instead of JMP and \
; branching to 3:1).

	.include "jbit.inc"

.code

quit:	lda	#0
show:	tax
	ldy	#0
L1:	sta	CONVIDEO,y
	clc
	adc	#1
	iny
	cpy	#40
	bne	L1
	txa
	ldy	#0
wait:	sty	FRMDRAW
	ldy	KEYBUF
	beq	wait
	cpy	#'2'
	beq	up
	cpy	#'8'
	beq	down
	cpy	#'0'
	beq	quit+1
next:	ldy	#1
	sty	KEYBUF
	bne	show
up:	cmp	#0
	beq	next
	sec
	sbc	#10
	bcs	next
down:	cmp	#220
	beq	next
	clc
	adc	#10
	bcc	next

charset.s