Timothy Miller wrote:
On 5/20/05, Eric Smith <[EMAIL PROTECTED]> wrote:All the ports are eight bits. I'm trying to find a reference to cite, but I believe doing a 16bit read of the VGA ports will result in getting either 0xFF in the high byte, or undefined garbage. Unlike a memory map, the high byte isn't filled with the contents of the next register.
Timothy wrote:
It appears that the extent of I/O space that is reserved for VGA isAFAIK, they are all 8 bit.
3B4h to 3DAh. Are they all bytes? Or are any 16-bit?
I think it won't be hard to deal with if someone does a 16-bit transaction, or even 32.
The VGA architecture is completely byte oriented. Even the mapped memory goes through a byte wide pipeline during reads and writes.
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