Bridgman, John writes:
I can do that next time I'm back home in two weeks. For my education, what is a TMDS, and hwat is TMDSA/LVTMA ?
TMDS (Transition Minimized Differential Signalling, I think) is the standard used to carry video and audio on a DVI or HDMI connector.
LVDS is a similar (but different) standard used to drive the panel in most laptops.
The TMDSA block is one of the encoder blocks in an ATI/AMD graphics chip which can drive one dual-link or two single-link TMDS outputs, depending on how it is configured. IIRC the "two single-link outputs" option is only available on 6xx and up.
We've actually seen no hardware where this is done and looking at the AtomBIOS parameter space for this block I cannot find any provision to do so. This was first introduced in the parameter space for the DIG blocks (DCE3). But wit DCE3 the TMDSA block went away.
The LVTMA block is a different encoder block on the same chip which can drive either an LVDS output or a TMDS output. The name comes from LVds + TMds.
The other common encoder is a DAC (Digital to Analog Converter), used to drive analog outputs.
One of the functions of the BIOS is to tell the driver how these different outputs are wired to connectors. Egbert was explaining that some of the connection information in the BIOS seemed not to match your description of the card, and in some cases did not even seem to make sense intuitively, eg. connecting the DAC (an analog output) to an HDMI connector (which only handles digital signals).
Yeah, there seems to be a separate VGA connector so what's sent to the HDMI connector currently is really sent to this. The interesting thing here is: both share a DDC line. The answer to this seems to be that one of the connectors lives on a docking station (don't remember which one). So when the machine is docked I assume the one on the machine is physically blocked. This way there is no way one can plug in both. Cheers, Egbert. -- To unsubscribe, e-mail: radeonhd+unsubscribe@opensuse.org For additional commands, e-mail: radeonhd+help@opensuse.org