emailler/drivers/a2print.s
Oliver Schmidt e54bb71bcc General source code cleanup.
- Tab chars were partially used with the unusual width of two blanks. I removed them altogether.
- Line endings were inconsistent even iniside individual files. I normalized them.
- I introduced a consistent coding style regarding comment indenting and blank line usage.
- I removed trailing spaces.
- I removed newlines following unnamed labels.
- ...
2013-12-27 14:57:56 +01:00

72 lines
1.8 KiB
ArmAsm

.export print_a
.export print_a_inverse
.export print_cr
.export cls
.export beep
.exportzp screen_current_row
.exportzp screen_current_col
.code
screen_current_col = $24 ; CH - Horizontal cursor-position (0-39)
screen_current_row = $25 ; CV - Vertical cursor-position (0-23)
; use Apple 2 monitor ROM function to display 1 char
; inputs: A should be set to ASCII char to display
; outputs: none
print_a:
ora #$80 ; turn ASCII into Apple 2 screen codes
cmp #$8A ; is it a line feed?
bne @not_line_feed
; jmp print_cr
pha
lda #$0
sta screen_current_col
pla
@not_line_feed:
jmp $fded
; use Apple 2 monitor ROM function to move to new line
; inputs: none
; outputs: none
print_cr:
jmp $fd8e
; use Apple 2 monitor ROM function to move to clear the screen
; inputs: none
; outputs: none
cls:
jmp $fc58
; use Apple 2 monitor ROM function to move to make a 'beep' noise
; inputs: none
; outputs: none
beep:
jmp $fbdd
print_a_inverse:
and #$7F ; turn off top bits
jsr $fded
; -- LICENSE FOR a2print.s --
; The contents of this file are subject to the Mozilla Public License
; Version 1.1 (the "License"); you may not use this file except in
; compliance with the License. You may obtain a copy of the License at
; http://www.mozilla.org/MPL/
;
; Software distributed under the License is distributed on an "AS IS"
; basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
; License for the specific language governing rights and limitations
; under the License.
;
; The Original Code is ip65.
;
; The Initial Developer of the Original Code is Jonno Downes,
; jonno@jamtronix.com.
; Portions created by the Initial Developer are Copyright (C) 2009
; Jonno Downes. All Rights Reserved.
; -- LICENSE END --