# HappyJon Demo
#
# Produced using "68k Mac boot floppy example" template
#
# Boot block header based on first/first.S
# from http://emile.sourceforge.net/
#

# The ROM loads this many bytes from the start of the disk.
..equ stage1_size, 1024

# Define ScrnBase, location in memory containing the start of video memory
..equ ScrnBase, 0x0824

# Macro to define a Pascal string
..macro pString string
pstring_begin_\@:
        .byte   pstring_end_\@ - pstring_string_\@ - 1
pstring_string_\@:
        .string "\string"
pstring_end_\@:
        .fill 16 - (pstring_end_\@ - pstring_begin_\@) , 1, 0
..endm

begin:

ID:          .short  0x4C4B              /* boot blocks signature */
Entry:       bra     start               /* entry point to bootcode */
Version:     .short  0x4418              /* boot blocks version number */
PageFlags:   .short  0x00                /* used internally */
SysName:     pString "Face Demo     "    /* System filename */
ShellName:   pString "Face Demo     "    /* Finder filename */
Dbg1Name:    pString "Face Demo     "    /* debugger filename */
Dbg2Name:    pString "Face Demo     "    /* debugger filename */
ScreenName:  pString "Face Screen   "    /* name of startup screen */
HelloName:   pString "Face          "    /* name of startup program */
ScrapName:   pString "Scrap         "    /* name of system scrap file */
CntFCBs:     .short  10                  /* number of FCBs to allocate */
CntEvts:     .short  20                  /* number of event queue elements */
Heap128K:    .long   0x00004300          /* system heap size on 128K Mac */
Heap256K:    .long   0x00008000          /* used internally */
SysHeapSize: .long   0x00020000          /* system heap size on all machines */

start:
	/* movel	#0x3FA700, %a0 */ /* Start of framebuffer on 4MB Plus */
	movel	(ScrnBase), %a0

	/* clear screen */
	movel	#0x00000000, %d0
	movel	#5472, %d1
clear_loop:
	movel	%d0, (%a0)+
	subi	#1, %d1
	bne	clear_loop

	/* Reset vars for image drawing: */
	lea	buffer, %a1 /* Image data */
	movel	(ScrnBase), %a0
	addal	#7388, %a0 /* Offset to place 64x64 image in center of display */
	movew	#127, %d1
fill_loop:

	movel	(%a1)+, %d0
	movel	%d0, (%a0)+

	/* mod buffer count to find offset and shift memory */
	movel	%d1, %d3
	divuw	#2, %d3
	andil	#0xFFFF0000, %d3
	bne	check_dec

	addal	#56, %a0	/* Move to next line */

check_dec:
	subi	#1, %d1
	bne	fill_loop

	/* One more time! */
	movel	(%a1)+, %d0
	movel	%d0, (%a0)+

	/* Set up an animation / prog indicator: */
	addal	#56, %a0	/* Move to next line */
	movel 	%a0, %a1
	addal	#4, %a1
	movel	#0xFF000000, %d0
	movel	#0x000000FF, %d2

end_loop:
	movel	%d0, (%a0)
	movel	%d2, (%a1)
	rorl	#1, %d0
	roll	#1, %d2
	movel	#10000, %d1
delay_loop:
	nop
	subi	#1, %d1
	bne	delay_loop
	bra	end_loop
end:

buffer:
	dc.l 0b00000000000000000000000000100001
	dc.l 0b11111100000000000000000000000000
	dc.l 0b00000000000000000000000000000011
	dc.l 0b11111100000000000000000000000000
	dc.l 0b00000000000000000000000000111111
	dc.l 0b11111110000000000000000000000000
	dc.l 0b00000000000000000000000001110000
	dc.l 0b01111110000000000000000000000000
	dc.l 0b00000000000000000000000011110111

	...
.