Re: winedos: Support reading from VGA register 0x3ba

[Michael Karcher]

Am Sonntag, den 06.07.2008, 13:45 -0700 schrieb Jon Griffiths:
> Title says it all.

> +        case 0x3ba:
> -
>        /* CRT status register (read only)
> -
>         * This register is read repeatedly to signal whether a hercules/
> -
>         * monochrome adapter is present, which is signalled by bit 7
> -
>         * changing within 0x8000 reads. The other bits then describe the
> -
>         * type of monochrome adapter present.
> -
>         */
> -
>        return 0; /* VGA compatible */

That patch seems wrong. As a VGA is able to coexist with a monochrome
adapter, it does not respond to reading 0x3ba at all. And ISA is TTL
compatible, i.e. open inputs read as one, so reads without responder
return 0xFF.

Regards,
  Michael Karcher