At any given time, data can be transferred between the master and one other device ( except for the little-used broadcast mode . ) The master chooses which slave device to address; typically, it switches rapidly from one device to another in a round-robin fashion.
12.
However, the choice of 64QAM broadcast mode, the fact that at least 40 % of homes would need new aerials to receive it, a high churn rate, an insecure hackable encryption system, the cost of having to provide free set-top boxes, and aggressive competition from BSkyB all contributed to ITV Digital's spiraling costs, before shareholders Granada and Carlton called a halt to the venture.
13.
Additional problems for ONdigital were caused by the choice of 64QAM broadcast mode, coupled with far weaker than expected broadcast power, ( meaning that the signal was weak in many areas ), a complex pricing structure ( comprising many menu options ), a poor quality subscriber management system ( badly adapted from Canal + ), a paper magazine TV guide whereas BSkyB had provided an signal piracy.
