1 # Test out the video mode by filling in the screen with pixels.
 2 #
 3 # To build a disk image:
 4 #   ./translate_subx_baremetal baremetal/ex2.subx    # emits disk.img
 5 # To run:
 6 #   qemu-system-i386 disk.img
 7 # Or:
 8 #   bochs -f baremetal/boot.bochsrc  # boot.bochsrc loads disk.img
 9 #
10 # Expected output:
11 #   html/baremetal.png
12 
13 main:
14   # ecx <- start of video memory
15   8b/-> *0x7f28 1/r32/ecx
16 
17   # eax <- final pixel of video memory
18   8d/copy-address *(ecx + 0x0bffff) 0/r32/eax  # 0xbffff = 1024*768 - 1
19 
20   # for each pixel in video memory
21   {
22     39/compare %eax 1/r32/ecx
23     7c/jump-if-< break/disp8
24     # write its column number to it
25     88/byte<- *eax 0/r32/AL
26     48/decrement-eax
27     eb/jump loop/disp8
28   }
29 
30   # hang indefinitely
31   {
32     eb/jump loop/disp8
33   }