Bochs VBE Extensions: Difference between revisions

The Bochs emulated graphics hardware (henceforth called BGA for Bochs Graphics Adaptor) is accessed via two 16-bit IO-ports. The first one is an index port, the second one a data port (comparable to how the VGA handles its sets of registers). Via these ports it is possible to enable or disable the VBE extensions, change the screen resolution and bit depth, and manage a larger virtual screen. There are six versions of the BGA (0xB0C0 through 0xB0C5), but if you use the latest version of Bochs you only need to concern yourself with the latest one (0xB0C40xB0C5). QEMU (with the -std-vga command line argument) also uses the latest version.