why Bitcoing mining hardware not supported from Hashcat

What is the reason that Hashcat does not support Bitcoing mining hardware?
(such cards seems to be very powerful AND energy-cost effective :-)

Thank's for any feedback!


e.g. something like http://www.butterflylabs.com/
1. BFL never responded to our request for dev hardware to test with.

2. ASICs would only be good for the algo that the gates are programmed for.