1 # pcboot - bootable PC demo/game kernel
2 # Copyright (C) 2018 John Tsiombikas <nuclear@member.fsf.org>
4 # This program is free software: you can redistribute it and/or modify
5 # it under the terms of the GNU General Public License as published by
6 # the Free Software Foundation, either version 3 of the License, or
7 # (at your option) any later version.
9 # This program is distributed in the hope that it will be useful,
10 # but WITHOUT ANY WARRANTY, without even the implied warranty of
11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 # GNU General Public License for more details.
14 # You should have received a copy of the GNU General Public License
15 # along with this program. If not, see <https://www.gnu.org/licenses/>.
18 .section .startup,"ax"
26 # move the stack to the top of the conventional memory
30 # zero the BSS section
41 # pcboot_main never returns
86 # calc src scanline address -> ebx
107 # calc src x offset -> eax
113 mov (%ebp, %eax), %cl
124 mov (%ebx, %esi), %al
141 # check for escape keypress