AppleCommander/build/AppleCommander-boot.s
Robert Greene 9bfb149930 Bootsector now rotates image and calls Apple reboot code in ROM.
The image data itself was compressed because of space issues.
This is exactly 256 bytes long.
2002-12-07 16:03:52 +00:00

1 line
2.0 KiB
ArmAsm

**********************************************************
* *
* APPLECOMMANDER boot code. *
* Copyright (c) 2002, Rob Greene *
* *
* This code is published under the GPL license. See the *
* AppleCommander site for license information. *
* *
**********************************************************
ORG $800
XEND = $2C
ADDR = $26
LINENO = $25
KEYBOARD = $C000
TEXT = $FB2F
HOME = $FC58
GR = $FB40
COLOR = $F864
HLIN = $F819
PRINT = $FDED
REBOOT = $FAA6
CALCADDR = $F847
DELAY = $FCA8
XOFFSET = 14
YOFFSET = 13
DFB 1 ; used by boot rom
JSR TEXT
JSR HOME
JSR GR
*
* Draw the AppleCommander logo (well, sorta)
*
LDX #DATA2-DATA1
:LOGO LDA DATA1-1,X
LSR
LSR
LSR
LSR
JSR COLOR
LDA DATA2-1,X
LSR
LSR
LSR
LSR
STA XEND
LDA DATA1-1,X
AND #$F
TAY
LDA DATA2-1,X
AND #$F
CLC
ADC #YOFFSET
JSR HLIN
DEX
BNE :LOGO
*
* Display AppleCommander text
*
:TEXT LDA MESSAGE,X
BEQ :WAIT
JSR PRINT
INX
BNE :TEXT
*
* Check for a keypress
*
:WAIT LDA KEYBOARD
BPL :SETUP
JMP REBOOT
*
* Rotate the screen (isn't that retro!)
*
:SETUP LDA #19
STA LINENO
:ROTATE JSR CALCADDR
LDY #0
LDA (ADDR),Y
PHA
:SHIFT INY
LDA (ADDR),Y
DEY
STA (ADDR),Y
INY
CPY #39
BNE :SHIFT
PLA
STA (ADDR),Y
DEC LINENO
LDA LINENO
BPL :ROTATE
*
* Introduce a pause between rotations
*
:KEYLOOP LDA #$08
JSR DELAY
DEX
BNE :KEYLOOP
BEQ :WAIT
* DATA1 consists of a color nybble and a x1 (start) position.
DATA1 HEX C8C7C6C3C8C2 ; green
HEX D1D1 ; yellow
HEX 9090 ; orange
HEX 1010 ; red
HEX 3131 ; purple
HEX 626368 ; blue
* DATA2 consists of x2 (end) and y position.
DATA2 HEX 90817253B3C4
HEX D5D6
HEX C7B8
HEX B9CA
HEX DBDC
HEX CD5EBE
MESSAGE ASC "THIS DISK CREATED WITH APPLECOMMANDER"8D
ASC "GET IT AT APPLECOMMANDER.SF.NET"8D
ASC " "8D
ASC "INSERT ANOTHER DISK AND PRESS ANY KEY"00