An arbitration controller that temporarily raises the priority of a graphic device's HWM request above that of the BitBLT engine while that device's LWM request is being served. In this manner, the BitBLT engine cannot interrupt the transfer of data to the graphics device. Each device capable...http://www.google.co.uk/patents/US5740383?utm_source=gb-gplus-sharePatent US5740383 - Dynamic arbitration priority
