diff options
Diffstat (limited to 'agbx/source/gfx/rd.s')
| -rw-r--r-- | agbx/source/gfx/rd.s | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/agbx/source/gfx/rd.s b/agbx/source/gfx/rd.s new file mode 100644 index 0000000..6662848 --- /dev/null +++ b/agbx/source/gfx/rd.s @@ -0,0 +1,32 @@ +@ Copyright 2022 Gabriel Jensen. +@ This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. +@ If a copy of the MPL was not distributed with this file, You can obtain one at <https://mozilla.org/MPL/2.0>. + +.syntax unified + +.cpu arm7tdmi +.thumb + +.globl ax_rd1 +.globl ax_rd2 + +.func +.thumb_func + +ax_rd1: + adds r0,r1 @ Get the address of the pixel by adding the offset to the video address. + ldrh r0,[r0] + bx lr + +.endfunc + +.func +.thumb_func + +ax_rd2: + adds r0,r1 @ Get the address of the pixel by adding the offset to the video address. + adds r0,r1 @ Add the offset twice as each pixel takes up two bytes. + ldrh r0,[r0] + bx lr + +.endfunc |