I forgot a couple of things:

> > option ROM_SIZE=256*1024

      You need something like this:

    option ROM_SIZE=256*1024-64*1024  # This assumes a 64K video BIOS

> The reason that they're different is that 12*65536 != 790528

>

> You should check the first few bytes of a video ROM to look for the

> signature (AA55)

Use

      hexdump | head

  or view it in a hex editor.

>

> You can also use strings. The ROMs I've seen have some recognizable

> strings in them.

Note that this needs to be coupled with looking for the signature to make sure that you're starting in the right place.

Hopefully when you build you'll have a (256-64)*1024 = 192K image that you can prepend your 64K Video BIOS to.

Myles